CAT 16H service manual

RENR5740-05 November 2003

Systems Operation Troubleshooting Testing and Adjusting 120H, 12H, 135H, 140H, 143H, 14H, 160H, 163H and 16H Motor Graders Caterpillar Monitoring System 1241-Up (Machine) 1251-Up (Machine) 1261-Up (Machine) CCA1-Up (Machine) CBC1-Up (Machine) ASD1-Up (Machine) ASE1-Up (Machine) CAF1-Up (Machine) CBK1-Up (Machine) ARL1-Up (Machine) APM1-Up (Machine) APN1-Up (Machine) CCP1-Up (Machine) ATS1-Up (Machine) AMX1-Up (Machine) ALZ1-Up (Machine) AMZ1-Up (Machine)

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Important Safety Information Most accidents that involve product operation, maintenance and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills and tools to perform these functions properly. Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information. Safety precautions and warnings are provided in this manual and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. The hazards are identified by the “Safety Alert Symbol” and followed by a “Signal Word” such as “DANGER”, “WARNING” or “CAUTION”. The Safety Alert “WARNING” label is shown below.

The meaning of this safety alert symbol is as follows: Attention! Become Alert! Your Safety is Involved. The message that appears under the warning explains the hazard and can be either written or pictorially presented. Operations that may cause product damage are identified by “NOTICE” labels on the product and in this publication. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The warnings in this publication and on the product are, therefore, not all inclusive. If a tool, procedure, work method or operating technique that is not specifically recommended by Caterpillar is used, you must satisfy yourself that it is safe for you and for others. You should also ensure that the product will not be damaged or be made unsafe by the operation, lubrication, maintenance or repair procedures that you choose. The information, specifications, and illustrations in this publication are on the basis of information that was available at the time that the publication was written. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete and most current information before you start any job. Caterpillar dealers have the most current information available.

When replacement parts are required for this product Caterpillar recommends using Caterpillar replacement parts or parts with equivalent specifications including, but not limited to, physical dimensions, type, strength and material. Failure to heed this warning can lead to premature failures, product damage, personal injury or death.

3 Table of Contents

Table of Contents Systems Operation Section

MID 030 - CID 0601 - FMI 08 MID 030 - CID 0615 - FMI 03 MID 030 - CID 0615 - FMI 04 MID 030 - CID 0819 - FMI 02 MID 030 - CID 0821 - FMI 03 MID 030 - CID 0821 - FMI 04

............................... ............................... ............................... ............................... ............................... ...............................

62 62 64 65 68 69

Diagnostic System Procedures Alert Indicator Is Always Flashing ......................... Alert Indicator Never Flashes ............................... Harness Code ....................................................... Pulse Width Modulated Sensor ............................ Sensor Signal Voltage .......................................... Sensor Dynamic Operation ................................... Fuel Level Sender ................................................. Switch Circuits ...................................................... Switch Circuits ...................................................... Charging System ..................................................

71 72 73 76 77 79 81 82 83 85

General Information ................................................ 4 Modes of Operation ................................................ 8 Normal Mode .......................................................... 9 Service Meter Mode .............................................. 10 Odometer Mode ..................................................... 11 Tachometer Mode .................................................. 11 Scrolling Mode ....................................................... 11 Harness Code Mode ............................................. 12 Numeric Readout Mode ........................................ 12 Additional Operator Modes ................................... 13 Service Mode ........................................................ 14 Tattletale Mode ..................................................... 16 Units Mode ............................................................ 18 Setup Mode .......................................................... 18 Calibration Mode ................................................... 18 Articulation Gauge Calibration Mode .................... 22 Warning Operation ................................................ 24 Alert Indicator Description ..................................... 25 Component Description ........................................ 27 Main Display Module ............................................ 27 Display Components ............................................. 31 Quad Gauge Module ............................................ 31 Speedometer/Tachometer Module ........................ 32 Switches ............................................................... 32 Senders ................................................................ 33 Sensors ................................................................. 34 Action Lamp .......................................................... 36 Action Alarm ......................................................... 36 Related Components ............................................ 37

Testing and Adjusting Section

Troubleshooting Section

Index Section

Introduction General Information .............................................. Service Tools ........................................................ Electrical Component and Connector Locations ... Diagnostic Capabilities .........................................

Testing and Adjusting System Self Test ................................................... 94 Wiring Harness (Open Circuit) - Test .................... 94 Wiring Harness (Short Circuit) - Test .................... 95 Wiring Harness (Short Circuit) - Test .................... 96 Electrical Connector - Inspect ............................... 96 Module - Replace .................................................. 97 Main Display Module Initialization - Adjust ........... 97 Main Display Module - Flash Program .................. 98 Glossary of Terms ................................................. 99 Connector Contact Description of Main Display Module ............................................................. 101 System Schematic .............................................. 104

Index ................................................................... 109 38 38 40 42

Diagnostic Code Procedures Diagnostic Code List ............................................. 44 Using Caterpillar Monitoring System to Determine Diagnostic Codes ................................................ 45 Using Caterpillar Electronic Technician to Determine Diagnostic Codes ................................................ 46 MID 030 - CID 0084 - FMI 08 ............................... 48 MID 030 - CID 0096 - FMI 03 ............................... 50 MID 030 - CID 0096 - FMI 04 ............................... 51 MID 030 - CID 0096 - FMI 08 ............................... 52 MID 030 - CID 0248 - FMI 02 ............................... 52 MID 030 - CID 0263 - FMI 03 ............................... 54 MID 030 - CID 0263 - FMI 04 ............................... 55 MID 030 - CID 0271 - FMI 03 ............................... 56 MID 030 - CID 0271 - FMI 05 ............................... 57 MID 030 - CID 0271 - FMI 06 ............................... 58 MID 030 - CID 0324 - FMI 03 ............................... 59 MID 030 - CID 0324 - FMI 05 ............................... 60 MID 030 - CID 0324 - FMI 06 ............................... 61

4 Systems Operation Section

Systems Operation Section i01853880

General Information SMCS Code: 7490

Introduction

Illustration 1 Caterpillar Monitoring System for the 140H, 143H, 160H and 163H The quad gauge module and the speedometer/tachometer module are optional components.

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Illustration 2 Caterpillar Monitoring System for the 14H and 16H The quad gauge module and the speedometer/tachometer module are optional components.

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Illustration 3 Caterpillar Monitoring System for the 12H, 120H and 135H The quad gauge module and the speedometer/tachometer module are optional components.

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The main display module is the brain of the system. This module receives information from the switches, sensors and other electronic controls on the machine via the CAT data link. The main display module processes all of the information. The module then activates various outputs. The outputs could be in the display area of the main display module, the quad gauge module, the speedometer/tachometer module, the action lamp, or the action alarm. The display components show the condition of the machine systems. The operator can also obtain system diagnostic information. The same monitoring system operates on a variety of different machines. All the possible system functions are not performed on every machine. After the main display module has been installed, the module recognizes the machine. The module will perform only the intended functions for that machine. The main display module is required for the monitoring system to operate. The quad gauge module and the speedometer/tachometer module may not be used on some machines. The maximum number of other modules that can be used with the main display module at any one time is four. The modules that can be used are two quad gauge modules and two speedometer/tachometer modules.

Main Display Module • The ten alert indicators (4) show abnormal conditions in the machine.

Illustration 4

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Typical Example Caterpillar Monitoring System Display Components (1) (2) (3) (4) (5) (6) (7) (8) (9)

Quad gauge module Speedometer/tachometer module Main display module Alert indicators Gauges Tachometer Speed readout Transmission gear readout Display area

The Caterpillar Monitoring System is an electronic monitoring system that continuously watches machine systems. The system is a flexible modular monitoring system that includes the following devices: a main display module, various switches and sensors, an action lamp, and an action alarm. The system may include a speedometer/tachometer module. A different number of quad gauge modules may be included in the system.

• A six digit display area (9) is provided. The

display shows the following modes: machine operational hours (service meter), engine speed (tachometer), machine distance (odometer), and diagnostic codes. The information for the speedometer/tachometer module, and any gauge of the quad gauge module can also be shown as a number on this readout. The display area contains seven unit indicators and a service indicator. The operator selects the information in order to be shown on the display area.

• Seven different unit indicators can be shown in

the display area. The unit indicators that can be shown are “°C”, “kPa”, “MILES”, “KM”, “RPM”, “LITERS” and “HOURMETER” symbol. These indicators show the units of measurement for the data on the six digit display area. The indicators are turned ON and OFF in order to correspond with the information on the six digit display area.

• In order to indicate a current fault, a service code

indicator is used. The service code indicator is used in service mode and diagnostic scrolling mode.

Speedometer/Tachometer Module • One tachometer gauge (6) shows the information on the engine speed (RPM).


• One three digit display area (7) shows the

information on the ground speed. The speed is displayed in “MPH” and “km/h”.

• Information on the transmission gear and the

direction are shown on a two digit gear readout (8).

Quad Gauge Module • The four gauges (5) show the condition of

the machine. The quad gauge will display the following information: engine coolant temperature, articulation angle, system voltage, and fuel level.

According to the application, the type and the quantity of indications that are used in the display areas varies. All of the indications are not used on the machine. The quantity of quad gauge modules and speedometer/tachometer modules may vary with each machine. An action lamp and an action alarm indicate the severity (warning category) of a problem. To determine the functions that are used on a particular machine, see the corresponding Operation and Maintenance Manual. i01962268

Modes of Operation SMCS Code: 7490

Illustration 5

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This is a typical example of the Display Area (Mode 2).

The Caterpillar Monitoring System has many different possible modes of operation. The modes are operator modes and service modes. Each mode provides important information regarding the condition of the machine. Each mode also provides information regarding the setup of the monitoring system. All modes are not available on all machines. The system that is installed on the machine determines the modes that are available. All the modes are given names and the modes are referenced in this manual. The mode is shown as a number on the display area of the main display module. This number is assigned by the software in the main display module.

The operator modes are accessible by using the selector switch for the operator mode that is located in the operator’s compartment. The following table shows the available modes. See the Operation and Maintenance Manual of the machine that is being serviced for specific information on the operator mode. When power is applied, the Caterpillar Monitoring System performs the self test. After the self test is complete the Caterpillar Monitoring System enters the Normal Mode. Normal Mode is service mode 0. Normal Mode contains the operator modes. In order to enter the other service modes, the service and clear inputs must be grounded at the same time. Access to the service and clear inputs is provided with the service connector. The service connector is located within the operator compartment. Information on the location of the service connector is in the Electrical System Schematic for the machine that is being serviced. When the service and clear inputs are grounded, the service mode numbers scroll sequentially on the six digit display area of the main display module. Note: When you are scrolling through the modes, mode 0 (Normal Mode) is not shown on the display area as a number. When you reach mode 0, the display area begins showing the information for mode 0 (Normal Mode). When ground is removed from the service and clear inputs, the monitoring system enters the mode which corresponds to the number that is presently shown. The following situation is an example. When you see the mode number “- 1-” on the display, remove the ground. This action causes the monitoring system to enter the Harness Code Mode. Note: The monitoring system must finish performing the self test before you ground the service and clear inputs in order to begin scrolling through the service modes.


Table 1

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12H, 14H, 16H, 120H, 135H, 140H, 143H, 160H And 163H

Normal Mode SMCS Code: 7490

Operator Modes Mode Number

Operator Mode Service Meter

0

Odometer

1

Digital Tachometer

2

Diagnostic Scrolling

3

Cumulative Fuel

4

Trip Machine Hours

5

Trip Odometer

6

Trip Fuel

7

Reset Trip Values

8

Table 2

12H, 14H, 16H, 120H, 135H, 140H, 143H, 160H And 163H Service Modes Service Mode

Mode Number

Harness Code

1

Parameter Display

2

Diagnostic Service

3

Tattletale

4

Digital Tattletale

4

Units

5

Calibration (Articulation Gauge)

6

Calibration (Transmission Control)

7

Calibration (Transmission Control)

8

Calibration (All Wheel Drive Control) (143H, 163H)

9

(1)

Setup

9

Setup (143H, 163H)

10

(1)

This mode is not operational at this time. This mode is reserved for future use.

Illustration 6

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Caterpillar Monitoring System Display Components (1) (2) (3) (4) (5) (6) (7) (8) (9)

Quad gauge module Speedometer/tachometer module Main display module Alert indicators Gauges Tachometer Ground speed readout Transmission gear readout Display area

Normal mode is used during normal machine operation. When you are in normal mode, the Caterpillar Monitoring System performs the following operations.

• A monitoring system that is operating properly

will perform a self test whenever the key switch is turned to the ON position. The outputs also operate for a brief instant. See Testing and Adjusting, “System Self Test ”.


• The main display module continuously watches

machine systems. If the gauges are available, the gauges in the quad gauge module show a value in a normal range. Ground speed readout (7) is shown as a numeric value and the transmission gear readout (8) on the module shows numeric values. The value for a condition may also be shown in the display area.

• The main display can show a problem with the

machine. The main display module continuously monitors machine systems. When an abnormal condition (problem) exists, the corresponding alert indicator (4) FLASHES. As the severity of the problem increases, the action lamp FLASHES and the action alarm SOUNDS. See System Operation, “Warning Operation”.

Note: The main display module may notify the operator when a diagnostic code exists in other electronic systems. This is done in different ways. The following example is of a diagnostic code that occurs in the engine electronic system. The service code indicator will show “SERV CODE” and the alert indicator for “check engine” FLASHES. See the Operation And Maintenance Manual for the machine that is being serviced for more specific information on the machine. Operator Modes Table 3

12H, 14H, 16H, 120H, 135H, 140H, 143H, 160H And 163H Operator Modes Operator Mode

Mode Number

The default condition is shown on the six digit display area when the main display module enters normal mode. This condition is normally the service meter. See System Operation, “Service Meter Mode” for more information. The six digit display area scrolls through the available operator modes when the operator switch input is grounded. Opening the switch input will stop the scrolling on the currently shown mode. Mode numbers are not displayed when operator modes are scrolling. See the topic with the corresponding name on the following pages for a more detailed explanation of each mode. Optional Machine Conditions The display area may be used to show other information on the condition of the machine. For example, the display area may be used as a gear readout when the speedometer/tachometer module is not used. The following situation occurs in order to function as a gear readout. The six digit display area changes from the default condition to the gear readout when the parking brake is DISENGAGED. The symbol for the service meter turns OFF and the information on the transmission gear is shown on the six digit display area. The display area may also be used when ether is being injected with a flashing “E”. A flashing “P” in the display area may be used when the engine is being prelubed. The following display modes are also available: the load count, the engine oil pressure, and the charge pressure. See the table for the Monitoring System Mode on the Electrical System Schematic in order to determine the mode number for the corresponding machine.

Service Meter

0

Odometer

1

Digital Tachometer

2

Diagnostic Scrolling

3

Cumulative Fuel

4

Service Meter Mode

Trip Machine Hours

5

SMCS Code: 7490

Trip Odometer

6

Trip Fuel

7

Reset Trip Values

8

The six digit display area (9) is used to show various conditions of the machine system to the operator (Operator Modes). Operator modes that are available to the operator are dependent to the monitoring system that is installed on the machine. The table above lists the operator modes by the machine.

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Illustration 7 Display Area

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The main display module keeps track of the total number of engine hours. The total machine operating hours are shown on the six digit display area when you are in service meter mode. The symbol for the service meter is ON in order to indicate when the display is functioning as a service meter. The value is continuously updated when the engine is operating. The main display module monitors the following electrical inputs in order to determine when the machine engine is operating: the engine speed, terminal for alternator “R”, and the engine oil pressure. The main display module starts the service meter for the machine when one of these inputs is in the normal range.

The engine RPM is shown on the six digit display area when the main display module is in tachometer mode. The indicator for the units shows “RPM”. The main display module can calculate engine speed with a frequency sensor. The main display module may also receive information from a frequency sensor from another electronic control module. This can be done by way of the CAT data link. i01456960

Scrolling Mode SMCS Code: 7490

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Odometer Mode SMCS Code: 7490

Illustration 8

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Display Area

The total distance for the machine is displayed on the six digit display area when the main display module is in odometer mode. The indicator for the units shows “MILES” or “KM”. This depends on the setting for units of measure of the main display module. The main display module receives information from the transmission output speed sensor from the transmission electronic control module. This is done by using the CAT data link. The unit of measure can be set by using the units mode. See Systems Operation, “Units Mode” for more information.

Illustration 10

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(1) First display. (2) Second display. (3) Module identifier (MID). (4) Service code indicator “SERV CODE”. (5) Component identifier (CID). (6) Failure mode identifier (FMI).

Scrolling mode allows service personnel or an operator to see diagnostic codes that were stored by the main display module. The diagnostic code in this mode can not be cleared. The diagnostic code can also not be placed on hold.

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The diagnostic codes momentarily scroll on the display area upon entering the scrolling mode. The MID is shown first as each diagnostic code is shown for about one second. The corresponding CID and the corresponding FMI is shown second for about two seconds. “End” appears when the last diagnostic code has been shown. The diagnostic codes are then shown. The display shows “- - -” when the main display module has no diagnostic codes.

Tachometer Mode SMCS Code: 7490


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The “SERV CODE” functions as a diagnostic present indicator in scrolling mode. The diagnostic that has caused a diagnostic code to be shown currently is present when “SERV CODE” is ON. “SERV CODE” is OFF when the fault is not present, but the fault has previously occurred.


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Harness Code Mode SMCS Code: 7490

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Harness code mode is always mode 1. The machine code is shown on the six digit display area when the main display module is in harness code mode. The machine code must correspond with the monitoring system that is installed on the machine sales model. See the following table for Machine Codes. The machine code is a two-digit representation of the harness code. An incorrect harness code is one that does not match the machine. Incorrect operation of the monitoring system will be caused by an erroneous harness code. Excessive diagnostic service codes could be recorded as a result of this situation. Table 4

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Numeric Readout Mode SMCS Code: 7490

Illustration 12

Machine Codes Sales Model

Some machines do not utilize a harness code plug. This can be verified with the electrical schematic for the machine. If the machine does not utilize a harness code plug, then the machine does not have a harness code. However, the machines that do not have a harness code will also display a machine code in harness code mode. The machine code does not represent the harness code in this case. The machine code represents the monitoring system configuration code. The monitoring system configuration code is configured in the software for the ECM with Caterpillar ET. The monitoring system configuration code is the numeric number in the sales model of the machine. For example, the monitoring system configuration code for a 160H is 160.

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Display Area

Machine Code

14H

14

140H

40

143H

43

160H

60

163H

63

120H

20

135H

35

12H

12

16H

16

Numeric readout mode is always mode 2. Numeric readout mode assists service personnel with troubleshooting of sensor inputs. The inputs supply information for the gauges in the quad gauge modules. Numeric readout mode more accurately shows the same information that is shown on the gauges in normal mode. The system identifier and the numeric value for the system scrolls on the six digit display area. The system identifier identifies the system that is currently shown on the six digit display area. See table 5 for “System Identification” and illustration 13 in order to match the system identifier to the appropriate gauge.


When you enter the numeric readout mode, the six digit display area is showing information for system GA-1. The display momentarily shows the system identifier. The display then shows the value for the corresponding system on the six digit display area. Grounding the service input causes all the systems to scroll on the display. This will show the system identifiers. Removing ground from the service input stops the scrolling, when the desired system is shown. The six digit display area continues to show the system identifier momentarily. The six digit display area then shows the value of the system. The system is now shown on hold. While the system is on hold, the numeric value of the system is continuously updated. i01525238

Additional Operator Modes g00789385

Illustration 13

Trip Hourmeter Mode

Quad gauge modules

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Illustration 14

This is an illustration of the display area on the Main Display Module that is showing an example of a system identifier. Table 5

System Identification System Identifier

Gauge (System)

GA-1

1

GA-2

2

GA-3

3

GA-4

4

Table 6

Units Condition Temperature Angle Voltage Level

SMCS Code: 7490

Units of Measurement °C ° 0.1 volts % full

In addition to the table and the illustration, only the gauge for the system that is shown on the six digit display area is operational. All other gauges in the quad gauge modules are shut off. The gauge needles will move to the far left position.

Illustration 15

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Display Area

The main display module keeps track of the trip hourmeter. The trip hourmeter will accumulate machine distance based upon the vehicle speed that is received from the transmission ECM. The total trip hourmeter is shown on the six digit display area when you are in trip hourmeter mode. The symbol for the trip hourmeter is ON in order to indicate when the display is functioning as a trip hourmeter. The value is continuously updated when the engine is operating. The main display module monitors the following electrical inputs in order to determine when the machine engine is operating: the engine speed, terminal for alternator “R”, and the engine oil pressure. The main display module starts the trip hourmeter for the machine when one of these inputs is in the normal range.


Trip Odometer Mode

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Service Mode SMCS Code: 7490

Illustration 16

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Display Area

The total distance for the machine is displayed on the six digit display area when the main display module is in trip odometer mode. The indicator for the units shows “MILES” or “KM”. This depends on the setting for units of measure of the main display module. The main display module receives information from the frequency sensor from the transmission ECM. This is done by using the CAT data link. The unit of measure can be set by using the units mode. See Systems Operation, “Units Mode” for more information.

Trip Fuel Consumption Mode Illustration 18

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Diagnostic Example (1) First display. (2) Second display. (3) Module identifier (MID). (4) Service code indicator (“SERV CODE”). (5) Component identifier (CID). (6) Failure Mode identifier (FMI).

Illustration 17

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Display Area

The fuel level is shown on the six digit display area when the main display module is in fuel level mode. The display will show “% full”, and no unit indicators are illuminated. The main display module calculates fuel level from a resistive sender, which is directly connected to the main display module.

Service mode is mode 3. The main display module detects faults that occur with sensor inputs, sender inputs, and main display module outputs while the main display module is in normal mode. The signal is at the contact of the main display module. A diagnostic code is detected when the signal is outside a valid range. The main display module then records the diagnostic code. The diagnostic code remains stored for future reference when the fault is not present. The main display module detects faults and the main display module diagnoses faults in the following circuits:

• Display output modules • Action alarm output • Action lamp output • Sensor input • Harness code Note: The main display module does not detect switch input faults.


Service personnel can see the diagnostic codes and service personnel can troubleshoot the diagnostic codes when the main display module has detected a fault. All detected faults are shown in the display area as a diagnostic code. The diagnostic codes can be placed on hold and the diagnostic codes can be cleared while the main display module is in service mode. Note: Diagnostic codes from other machine systems under electronic control are shown in the display area of the main display module when the main display module is in Service Mode. The CAT data link allows the transfer of diagnostic information from other electronic control modules to the main display module. This diagnostic information is then shown when the main display module is in service mode. The diagnostic code for faults from other electronic control modules has a MID that is unique to the control. These diagnostic codes can scroll similarly to the diagnostic codes from the Caterpillar Monitoring System. See the following description of Module Identifier (MID). The diagnostics of the Caterpillar Monitoring System are available to assist with the troubleshooting of diagnostic codes when the main display module is placed in service mode. A diagnostic code is used to specify each fault. The diagnostic code is made up of three identifiers (MID, CID and FMI). These identifiers are shown in the display area. The display area continuously changes between the following identifiers when the diagnostic code is on hold: Module Identifier (MID) – The MID is a three-digit code that is shown on the display area. The MID is shown for approximately one second before the diagnostic code that is shown in the same area. The electronic control module that has diagnosed the diagnostic code is logged by the MID. The following examples are of some MID. Caterpillar Monitoring System ...................... Engine Control (ADEM) ................................ Power Train Electronic Control System ........ All Wheel Drive Electronic Control System ...

030 036 081 075

See the table for the Module Identifier (MID) on the Electrical System Schematic for the machine that is being serviced for the most complete list. To troubleshoot diagnostic codes, use the service manual for the control that detected the code.

Component Identifier (CID) – The components that are faulty are noted by the CID. These components are examples: transmission oil temperature sensor, speed sensor, action lamp, and boost pressure sensor. The CID is a four digit code that is shown on the six digit display area. The CID and the FMI are shown together after the MID has been displayed. See the table “Diagnostic Codes For Caterpillar Monitoring System” in Testing And Adjusting, “Troubleshooting Diagnostic Codes”. This will show a list of CID codes for the main display module. Failure Mode Identifier (FMI) – The FMI tells the type of failure that has occurred. The following situations are examples: voltage above normal, current below normal, and abnormal frequency. The FMI is a two digit code that is shown on the six digit display area. The CID and the FMI are shown after the MID is displayed. The CID and the FMI are separated by a decimal point “.”. See the table “Diagnostic Codes For Caterpillar Monitoring System” in Testing And Adjusting, “Troubleshooting Diagnostic Codes”. This table will show a list of failure mode identifiers for the main display module. When the main display module enters the service mode, the MID, the CID, and the FMI are shown. At this time, the diagnostic code that is shown is on hold. The display area continuously changes between the following identifiers when the diagnostic code is on hold: MID, CID, and FMI. This is maintained as long as the service and clear inputs remain open. Troubleshooting is performed while the diagnostic code is on hold. Note: The display shows “- - -” when the main display module has no diagnostic codes. All diagnostic codes are shown one at a time in the display area when the diagnostic codes are scrolling. Grounding the service input causes the display to scroll when the main display module is in service mode. This will momentarily show the MID. The display will show the CID and the FMI that corresponds. Removing ground from the service input stops the scrolling when the diagnostic code that is desired is shown. The diagnostic code that is shown is now on hold. Note: The diagnostic codes from other electronic control modules can be shown on the display. Use the same procedure in order to place the diagnostic codes on hold.


Diagnostics are provided in order to assist service personnel during troubleshooting of intermittent faults. The service code indicator “SERV CODE” is shown when the diagnostic code is present. This can aid in troubleshooting of intermittent faults. The service code indicator changes from “SERV CODE” that is OFF to “SERV CODE” that is ON. This will occur when the fault changes status. The action alarm SOUNDS briefly during the change of status when the diagnostic code is on hold for a fault. These diagnostics signal the service personnel while inspections are performed. These diagnostics assist in troubleshooting intermittent faults by one service person. A diagnostic code is removed from the memory of the main display module when the diagnostic code has been cleared. When a fault is corrected, it is necessary to remove the corresponding diagnostic code from the memory of the main display module. In order to remove the diagnostic code from the memory, place the diagnostic code on hold and ground the clear input. The memory of the main display module saves a diagnostic code until the code is cleared. The main display module does not allow clearing of a diagnostic code that corresponds to a fault which is present. Note: The diagnostic codes from other electronic control modules should be cleared by using the main display module.

Illustration 19 shows a main display module that is currently receiving a signal. This signal is from the transmission oil temperature sensor and the signal is out of range. Detailed Explanation MID (3) – “030”. This code concerns the Caterpillar Monitoring System. The Caterpillar Monitoring System service manual should be used to troubleshoot the diagnostic code. If the MID that was shown was “081”, the diagnostic code would concern the power train electronic control. The service module for the power train electronic control should be used to troubleshoot the diagnostic code. CID (5) – “0110”. This code means that a fault has occurred in the sensor circuit for the engine coolant temperature of MID “030”. See the table for Detected Faults in Testing And Adjusting, “Troubleshooting Diagnostic Codes”. This will show a list of CID codes for the Caterpillar Monitoring System. FMI (6) – “08”. This identifier means that a signal of abnormal frequency, pulse width or period is being received concerning CID “0110”. See the table for Detected Faults in Testing And Adjusting, “Troubleshooting Diagnostic Codes”. This table will show a list of FMI codes for the Caterpillar Monitoring System. Service code indicator (4) is ON in Illustration 19. When the main display module is in service mode, the service code indicator (4) functions as a fault present indicator. Therefore, the CID “0110” fault is present. The service code indicator changes from ON to OFF when the CID “0110” fault changes status. Also, the action alarm sounds when the CID “0110” fault changes status. This action will take place while the main display module is in service mode. i01520269

Tattletale Mode SMCS Code: 7490

Illustration 19

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Diagnostic Example (1) First display. (2) Second display. (3) Module identifier (MID). (4) Service code indicator (“SERV CODE”). (5) Component identifier (CID). (6) Failure Mode identifier (FMI).

Brief Explanation


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Gauges (5) show the highest reading or lowest reading that has been attained by the corresponding machine system. The gauges show the highest reading for systems with increasing abnormal values. The gauges also show the lowest reading for systems with decreasing abnormal values. The gauge alternates between the highest reading and lowest reading. This will occur for the gauges that are double ended. Tachometer (6) and speed readout (7) show the highest reading that has been obtained. Alert indicators (4) turn on when an abnormal condition has existed. Information from the tattletale is retained until the information is cleared. Grounding the clear input erases the information. After clearing, all information is reset to a nominal value and the recording of new extreme values begins. Note: The date, time or duration of the extreme value that has occurred is not recorded. Example This example explains the information that is shown in the illustration for the Tattletale Mode.

• Gauge (5) for the engine coolant temperature has a pointer that indicates a value above the normal temperature range. Therefore, a high abnormal value has existed in this system.

Illustration 21

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Caterpillar Monitoring System Display Components (1) (2) (3) (4) (5) (6) (7) (8) (9)

Quad gauge module Speedometer/tachometer module Main display module Alert indicators Gauges Tachometer Speed readout Transmission gear readout Display area

Tattletale Mode is a tool for management and maintenance. The history of the machine can be recorded by this mode. The main display module records the extreme value for each condition of the machine that is monitored. The values come from sensor inputs, switch inputs and the CAT data link. The values in tattletale mode are updated whenever a value occurs with more importance than the previous value. These values are ignored for a short period of time after each start-up. This allows the machine systems to stabilize before the recording of information.

• Gauge (5) for the battery charge level has a pointer that indicates a value below or a value above the normal battery charge range. Therefore, a low abnormal value or a high abnormal value has existed in this system.

• Gauge (5) for the articulation angle has a pointer that indicates a value for the articulation angle of the machine. Therefore, no abnormal value has existed in these systems.

• Gauge (5) for the fuel level has a pointer that

indicates a level of 50%. Therefore, the highest amount of fuel that has existed is 50%.

• The pointer on tachometer (6) indicates a

maximum value (2100 RPM). Therefore, an engine speed of 2100 rpm has existed.

• Speed readout (7) shows “13 MPH”. Therefore, 13 MPH is the highest ground speed that has been attained.

• Alert indicator (4) is ON. Therefore, an abnormal condition has existed in this system.

• All other alert indicators (4) are OFF. Therefore, no abnormal values have existed in these systems.


Note: No information from the tattletale mode is stored for the highest transmission gear or lowest transmission gear that has been selected.

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Setup Mode SMCS Code: 7490

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Units Mode SMCS Code: 7490

Illustration 23

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Display Area

Illustration 22

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Caterpillar Monitoring System (1) Speedometer/tachometer module. (2) Main display module. (3) Odometer units. (4) Speed readout. (5) Speedometer units. (6) Display area. (7) Six digit display area.

The units mode is mode 5. The units mode is used to toggle the displays of the monitoring system between US and Metric units of measure. When the main display module enters units mode, six digit display area (7) shows the current setting. The display reads “US” when the mode is set to US units. The display reads “SI” when the mode is set to Metric units. When the units mode is set to US units, the main display module shows “MILES” on display area (6) when the main display module is in odometer mode. The display for the speedometer/tachometer module shows “MPH”. The display area (6) shows “KM” when the main display module is set to Metric units. The display for the speedometer/tachometer module shows “km/h”. In order to toggle the units, ground the clear input while the service input is open. The units continuously toggle when the clear input is grounded. Opening both of the inputs will set the main display module to the currently displayed setting.

Setup Mode is mode 9 on all of the motor graders except the 143H and the 163H. Setup Mode is mode 10 on the 143H and the 163H. This mode is used in order to configure the installation status of the speedometer/tachometer module. If the speedometer/tachometer module is already installed, the display will read “t1 YES” when you enter the Setup Mode. If the speedometer/tachometer module is not installed, the display will read “t1 NO”. In order to change the status of the module, ground the clear input for two seconds. If multiple speedometer/tachometer modules are present on the machine, grounding the service input for two seconds will display the status of the next module. For example, the display may read “t2 YES”. The display will read “END” once you have scrolled through all of the modules. Grounding the service input for two seconds will start scrolling through the status of the modules again from the first module. i01963535

Calibration Mode SMCS Code: 7490 Calibration Mode 7 and Calibration Mode 8 are associated with the power train ECM. Calibration Mode 7 and Calibration Mode 8 are identical. Both modes contain the same submodes and perform the same calibrations. Calibration Mode is used on some machines in order to perform special functions of calibration. The operation of the Calibration Mode will vary depending on the machine and the system that is being calibrated. The Service Manual Module for the controls that require the Calibration Mode should be used in order to determine the operation.


Submodes

E04 – The calibration value is too small.

Calibration Mode 7 and Calibration Mode 8 include submodes in order to extend the diagnostic capabilities. After you have entered mode 7 or mode 8, use the service switch in order to scroll through the submodes.

The error codes indicate that the inching pedal position sensor may be adjusted improperly. Perform the Testing and Adjusting, “Inching Pedal - Adjust” procedure in this manual and then repeat the calibration procedure.

Submode 7.29 / 8.29 (Calibration Of The Inching Pedal Position Sensor ) This procedure allows the calibration of the travel limits of the inching pedal position sensor. The inching pedal must be calibrated if any of the conditions that are listed below have occurred:

• The power train ECM has been replaced. • New software has been flashed into the power

train ECM and a diagnostic code of CID 0573 FMI 13 is active.

• The position sensor for the inching pedal has been replaced.

• The linkage for the inching pedal has been adjusted.

6. Exit submode number 29 by scrolling to the next submode number by using the “SCROLL” switch or by exiting the “Power Train Calibration” mode by using the “Mode” Switch.

Calibration Of The Engagement Pressure For The Transmission Clutch Incorrect transmission clutch pressure adversely affects the life of the transmission. Submodes 31 through 33 are used in order to set the transmission clutch pressure of the direction clutches (No. 1 through No. 3). In this process, the service technician adjusts the electrical current that is sent to the transmission solenoid valve in order to obtain the specified pressure for the transmission clutch. The calibration of the transmission clutch pressure must be performed prior to the transmission clutch fill calibration (submode 40).

1. Connect the 4C-8195 Control Service Tool to the service tool connector.

The transmission system must be calibrated if any of the following conditions have occurred:

2. Use the 4C-8195 Control Service Tool in order to enter the “Power Train Calibration” Mode (7) via the “MODE” switch. Then use the “SCROLL” switch to enter submode number 29.

• A transmission solenoid valve has been replaced

3. Ensure that the inching pedal is not pressed. Use the “INCREMENT (+)” position of the “CLEAR” switch to start the calibration. The display on the 4C-8195 Control Service Tool will change to “C01”.

• New flash software has been flashed into the ECM.

4. Press and hold the inching pedal to the down limit. Select “INCREMENT (+)” position of the “CLEAR” switch. The display on the 4C-8195 Control Service Tool will change to “C02”. 5. Release the inching pedal. Select the “INCREMENT (+)” position of the “CLEAR” switch. The display on the 4C-8195 Control Service Tool will change to “---” if the calibration was successful. If an error occurred during the calibration, The display on the 4C-8195 Control Service Tool will change to “Exx”. The “xx” is one of the failure codes that are listed below: E01 – The calibration value is too high. E02 – The calibration value is too low. E03 – The calibration value is too large.

or cleaned.

• A different power train ECM has been installed.

• A transmission clutch has been rebuilt. • The transmission clutch does not shift correctly.


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Illustration 24 Transmission Clutch Solenoid Valves (1) Transmission solenoid valve (No. 3) (2) Transmission solenoid valve (No. 1) (3) Transmission solenoid valve (No. 2)

(4) Transmission solenoid valve (No. 8) (5) Transmission solenoid valve (No. 4) (6) Transmission solenoid valve (No. 6)

Table 7

Error Codes for the Calibration of the Transmission Clutch E01

The Clutch Solenoid or the Speed Sensor has an Active Fault.

E02

The Inching Pedal was not released when you entered the Submode.

E03

Active Fault For the Position sensor (Inching Pedal)

E04

The Transmission Lever is Not in the PARK Position.

E05

Temperature of the Transmission Oil is Below the Fault Threshold. (60 °C (140 °F))

E06

The Engine Speed is Below the Fault Threshold of 1800 rpm.

E09

Machine Speed Is Not Zero.

During calibration of the transmission clutch pressure, error codes (EXX) can occur. The error codes will appear in the display area of the Caterpillar Monitoring System. The error codes will appear if a problem occurs during the calibration.

(7) Transmission solenoid valve (No. 5) (8) Transmission solenoid valve (No. 7)

For more information on the calibration procedure, refer to the Testing and Adjusting, RENR4104, “Engagement Pressure for the Transmission Clutch - Calibrate”.

Submode 7.40 / 8.40 (Transmission Clutch Fill Calibration) Improper calibration of the transmission clutch fill will cause transmission shifting problems. The automatic calibration procedure for setting the transmission clutch fill will achieve greater consistency. The calibration of the transmission clutch engagement pressure (submode 31 through submode 33) should be performed prior to the calibration of the transmission clutch fill (submode 40). During the transmission clutch fill calibration (submode 40), error codes (EXX) can occur. The error codes will appear in the display area of the Caterpillar Monitoring System. The error codes will appear if a problem occurs during the calibration or if there is a problem with the results of the calibration.


Table 8

Error Codes for the Calibration of the Transmission Clutch Fill E01

The Clutch Solenoid or the Speed Sensor has an Active Failure.

E04

The Transmission is Not in the Park Position.

E05

The Temperature of the Transmission Oil is Below the Fault Threshold. (68 °C (154 °F))

E06

The Engine Speed is Below the Fault Threshold of 1800 rpm.

E09

Machine Speed Is Not Zero.

E11

Calibration of the Engagement Pressure Is Not Completed.

E21

Number 1 Clutch at a Limit

E22


E23


The calibration software may need to adjust one of the parameters beyond the limit of the design specification. In this case, error codes E21, E22, or E23 will appear in the display area after the calibration procedure is complete. The software will select the best values, but the error code indicates that an error exists in either the conditions for calibration or the transmission system. If error codes E21 through E23 are displayed, check the following conditions for the source of the error:

• Make sure that the transmission oil and the

transmission components are fully warmed in order to run the calibration.

• Make sure that the transmission solenoid valves

are correctly torqued. (Make sure that the valves are cool when the valves are torqued.)

• Worn seals are causing leakage. • The clutch is worn beyond the allowable range. • The transmission solenoid valve is damaged. • A new transmission solenoid valve was not energized sufficiently.


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Illustration 25 Transmission Solenoid Valves (1) Transmission solenoid valve (No. 3) (2) Transmission solenoid valve (No. 1) (3) Transmission solenoid valve (No. 2) (4) Transmission solenoid valve (No. 8)

(5) Transmission solenoid valve (No. 4) (6) Transmission solenoid valve (No. 6) (7) Transmission solenoid valve (No. 5) (8) Transmission solenoid valve (No. 7)

Note: If a new transmission solenoid valve was installed, you must shift the transmission into a speed or a direction that uses the transmission solenoid valve. The transmission must be shifted at least 12 times. Refer to Illustration 25 in order to identify the transmission solenoid valve and the corresponding clutch. Allow sufficient time for the corresponding clutch to be fully pressurized. During the transmission clutch fill calibration, error codes (EXX) can occur. The error codes will appear in the display area of the Caterpillar Monitoring System. The error codes will appear if a problem occurs during the calibration or if there is a problem with the results of the calibration. If there are no problems or if the problems are fixed, run the calibration (submode 40) again. For more information on the calibration procedure, refer to the Testing and Adjusting, RENR4104, “Fill Time for the Transmission Clutch - Calibrate”.

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Articulation Gauge Calibration Mode SMCS Code: 7490 The 4C-8195 Service Tool allows personnel to access information that is related to service. The service tool attaches to the connector that is located behind a plate directly below the Caterpillar Monitoring System. The connector has four pins. In order to calibrate the articulation gauge needle, enter mode 6 and perform the following procedure: 1. Attach the service tool to the service mode connector on the Caterpillar Monitoring System.


Note: If the needle appears centered, the switches must be pressed in order to record the articulation sender resistance.

Illustration 26

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Display Area (Mode 6)

2. Press up both the service “SCROLL” and “CLEAR” switches on the service tool. When both switches are pressed, the Caterpillar Monitoring System will scroll to different display modes in the display area. Display mode 6 is used to calibrate the articulation gauge needle. The two switches should be held until the Caterpillar Monitoring System display area shows “-6-”.

Illustration 27

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Up Stop Display

3. Pressing and releasing the “SCROLL” switch will move the needle to the right one degree at a time. When the value is changed, the needle will move one degree, and a up arrow will flash once on the display. The amount of adjustment is limited to 10 degrees from the default. If this limit has been reached, a up stop will flash once on the display.

Illustration 28

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Down Stop Display

4. Pressing and releasing the “CLEAR” switch will move the needle to the left one degree at a time. When the value is changed, the needle will move one degree, and a down arrow will flash once on the display. The amount of adjustment is limited to 10 degrees from the default. If this limit has been reached, a down stop will flash once on the display. 5. When the needle appears centered, exit the calibration mode.


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Warning Operation SMCS Code: 7490 Table 9

WARNING OPERATION Warning Indications Warning Category

“Alert Indicator Flashes ”(3)

1

X

2

X

X

(4)

2-S

X

X

(4)

X

3

X

X

(4)

X

(1) (2) (3) (4) (5) (6)

“Action Lamp Flashes”(4)

(1)

“Action Alarm Sounds ”

“Operator Action Required”

“Possible Result ”(2)

No immediate action is required. The system needs attention soon.

No harmful effects or no damaging effects.

Change machine operation or perform maintenance to the system.

Severe damage to components can occur.

(5)

Immediately change the machine operation.

Severe damage to machine components

(6)

Immediately perform a safe engine shutdown.

Injury to the operator or severe damage to components can occur.

The active warning indications are marked with an X. This is the possible result if no action is taken by the operator. The alert indicator flashes at a 8 Hz rate. The action lamp flashes at a 1 Hz rate (1 second ON, 1 second OFF). Steady The action alarm sounds at a 1 Hz rate (1 second ON, 1 second Off).

Illustration 30 Speedometer/Tachometer Module (3) (4) (5) (6) Illustration 29 Quad Gauge Module (1) Gauge warning area (2) Pictograph symbol

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Tachometer Pictograph symbol Ground speed readout Transmission gear readout

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The Category 2-S is a conventional Category2 with a continuous action alarm. A Category 2 that is considered to be a severe condition will cause a category 2-S to be logged. A Category 2 tells the operator to change machine operation in order to correct the warning condition. The operator is instructed to IMMEDIATELY change operation of the machine that relates to certain Category 2-S events. Note: Most category 3 events cannot be acknowledged by the operator. Note: See the Operation And Maintenance Manual for complete information on the Warning Operation. Illustration 31

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Main Display Module (7) Alert indicator (8) Display area

The Caterpillar Monitoring System notifies the operator of an immediate problem with a machine system or an impending problem with a machine system. Warning operation begins when the main display module receives a problem signal. The problem signal reflects an abnormal condition of the machine. Warning operation also begins when the main display module detects a problem with the control system. Switches, sensors, and other electronic control modules on the machine provide signals to the main display module. The problem signals are the following conditions:

Alert Indicator Description SMCS Code: 7490

• An open switch. When a condition exceeds the trip point of the switch, the switch opens.

• A sensor signal exceeds the limits. The main display module determines the limits.

• Another condition is an abnormal condition that is

detected by another electronic control module. The abnormal condition is then communicated over the CAT data link to the main display module.

The main display module analyzes the problem signals. In order to notify the operator of a warning, the display components on the main display module activate the appropriate warning indication. The following warning indications will notify the operator:

• The alert indicator FLASHES approximately nine times per second.

• The action lamp FLASHES for one second and the action lamp is OFF for two seconds.

• The action alarm SOUNDS for one second and the action alarm is OFF for two seconds.

Note: In order to activate warning indications, more than one input is required. The main display module decides when the warning indications are activated.

Illustration 32 Alert Indicators For 143H And 163H (1) Hydraulic Oil Temperature (2) Parking Brake Status (3) Charging System Status (4) All Wheel Drive Status (5) Check Engine Status (6) Engine Coolant Temperature (7) Steering System Status (8) Engine Oil Pressure (9) Brake Air Pressure (10) Transmission System Status

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Illustration 33

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Illustration 34

Alert Indicators For 140H, 160H, 12H, 120H And 135H

Alert Indicators For 14H And 16H

(1) Hydraulic Oil Temperature (2) Parking Brake Status (3) Charging System Status (4) Unused (5) Check Engine Status (6) Engine Coolant Temperature (7) Steering System Status (8) Engine Oil Pressure (9) Brake Air Pressure (10) Transmission System Status

(1) Hydraulic Oil Temperature (2) Parking Brake Status (3) Charging System Status (4) Unused (5) Check Engine Status (6) Engine Coolant Temperature (7) Steering System Status (8) Engine Oil Pressure (9) Brake Air Pressure (10) Unused

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Hydraulic Oil Temperature – This light will indicate that the hydraulic oil temperature is greater than 100 °C for the 14H, 140H and the 160H. This light indicates that the hydraulic oil temperature is greater than 88 °C for the 143H and the 163H. The temperature is received from the hydraulic oil temperature sensor. Parking Brake Engaged – The light indicates that the parking brake is engaged. Parking brake status is received over the data link. The information is used to modify the warning level of this indicator. If the machine is in neutral, only the indicator lights. However, if the machine is in a forward gear or a reverse gear, the action lamp and the action alarm also activates.


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Charging System Status – The light indicates that battery voltage is outside the range of 24.8 to 29.5 DCV. While the engine is running, the light also turns on when the alternator frequency is below 90 Hz. In addition to the lighting of the indicator, the action lamp and the action alarm will also activate when the battery voltage rises above 32 DCV.

Main Display Module SMCS Code: 7490

Check The Engine – This application is used with HEUI engines. The light indicates that the engine system requires service. The status is received from the engine ECM via the CAT data link.

data link.

Steering System Status – The light indicates that the primary steering pressure is low. The pressure is received via the CAT

Illustration 35

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Main Display Module

Low Engine Oil Pressure – This light indicates that the engine oil pressure is low. This signal is received by the Caterpillar Monitoring System from the engine ECM via the CAT data link. The indicator lights when the switch voltage is high or the switch voltage is floating. Transmission System Status – The light indicates that the transmission conditions are not working properly. The information is received from the power train ECM via the CAT data link. i01862477

Component Description SMCS Code: 7490 This arrangement of the Caterpillar Monitoring System will work on the current Motor Graders. Three modules constitute the Caterpillar Monitoring System: main display module, quad gauge module, and speedometer/tachometer module. All of the following electrical components are not present on every machine. The main display module recognizes the machine and the components that are present. For the location of the electrical components, see the Electrical System Schematic in the Service Manual for the machine.

(1) Alert Indicators. (2) Display area.

The main display module continuously monitors all machine systems. The main display module makes decisions that are based upon the input from the machine systems or other electronic control modules. The main display module sends information to other electronic controls on the machine. The input and output of this information takes place over the CAT data link. The outputs on the main display module notify the operator and the service person of the status of the machine systems. The following outputs are on the Caterpillar Monitoring System: the quad gauge, the speedometer/tachometer module, the main display module, the action lamp, and the action alarm. A connector with 40 contacts is located on the rear of the module. This connector connects the necessary harness wiring to the inputs and outputs. For a complete description of the connector, see Testing And Adjusting, “Connector Contact Description of Main Display Module”.

Inputs/Outputs CAT Data Link The CAT data link (connector contacts 5 and 14) is used to communicate with other electronic control modules on the machine. The CAT data link is bidirectional. This allows the modules to input the information. Also, the modules can output the information. This permits sharing of information such as engine oil pressure, harness codes and diagnostics.


Display Data Link

Switch Inputs - Uncommitted

The display data link (connector contacts 15, 25 and 35) provides the electrical signals in order to operate the speedometer/tachometer module and the quad guage module. These display modules provide information about the machine systems to the operator. Each module and each display indicator is identified by an identifier or an address. Data is continuously output from the main display module to the other display modules. The module that is addressed returns the data to the main display module. This confirms the receipt of the data.

The uncommitted switch inputs (connector contacts 11, 19, 20, 21, 29, 32, 39, and 40) provide the information that is used in order to operate the ten alert indicators. The alert indicators are part of the outputs on the main display module. These switch inputs may be programmed at the time of installation to work independently. The switch inputs may be programmed with other switch inputs and/or sensor inputs. The switch inputs will operate an alarm indicator and the input will determine the appropriate warning category (1,2 or 3). During normal operation, these switch inputs are closed to ground. The grounded inputs tell the main display module that the conditions of the system are normal and no alert indicators should be ON. These inputs receive information from the following switches that are located within the machine systems: pressure, temperature, flow, level, and mechanical.

Inputs The operation and the status of the machine is transferred from the inputs to the main display module. Three types of inputs exist: switch type input, sensor type input, and sender type input. Switches and harness wiring provide a ground or an open signal to the switch inputs. Sensors provide a changing signal to the sensor inputs of the main display module. Senders provide a changing resistance to the sender inputs of the main display module. Some inputs are multipurpose (switch, sensor or sender). The following examples are of multipurpose inputs: connector contacts 7, 17, 27 and 37 may be either switch inputs or PWM sensor inputs, connector contacts 9 and 18 may be either switch inputs or 0-240 ohm sender inputs, and connector contacts 8, 10, 28 and 38 may be switch inputs, PWM sensor inputs or 70-800 ohm sender inputs. These inputs are programmed at the time of installation in order to define the components that are monitored. In order to determine the inputs on the main display module that are programmed, see the Electrical System Schematic in the Service Manual.

Other inputs for the main display module may be programmed at the time of installation in order to function as uncommitted switch inputs. For more information, see the topics “Sensor Inputs - PWM”, “Sender Inputs - 0-240 ohm” and “Sender Inputs 70-800 ohm”. Any one of the switch inputs may be programmed to operate from an operator switch that is used to operate the display area on the main display module. For the location of this switch input, see the wiring diagram for the machine. For information on the operation of this switch, see System Operation, “Normal Mode”. Note: The alert indicators may also be programmed to operate from sensor inputs. One of the ten alert indicators is normally dedicated to the charging system. The system uses the input for the battery power and the input for the alternator terminal “R”.

Switch Inputs - Programming The operation of the main display module is determined by the programming switch inputs (connector pins 3, 6, 12, 16, 22 and 31). The main display module operates in a manner that corresponds to the open state or the grounded state of the programming switch inputs. These inputs receive information from a permanent connection or a harness code connector within the harness wiring. The inputs for the programming switch consist of the information from the harness code. The inputs from the harness code switch tell the main display module the machine model. Information of the model is necessary because of the differences in the machines. Information from the machine is necessary for the main display module to make decisions.


Switch Inputs - Service The inputs from the service switches (connector contacts 23 and 33) control the setup, the mode of operation, and certain diagnostic functions. Grounding the service input (connector contact 23) and the clear input (connector contact 33) at the same time will initiate a change in the monitoring system mode of operation. Removing ground from these two inputs locks the main display module in the selected mode. Other diagnostic functions are also performed when the service inputs are grounded and/or opened at the proper time. For more information, see System Operation, “Modes Of Operation”.

Sensor Inputs - PWM Each PWM sensor input (connector contacts 7, 17, 27 and 37) may be programmed in order to operate as either a sensor input or a switch input. A PWM signal is present when the sensor input is programmed to operate as a PWM sensor input. A PWM signal represents the condition of a machine system. As the condition of the machine changes, the duty cycle of the signal changes. The duty cycle is the percentage of time that the signal is ON compared to the time the signal is OFF. The frequency of the signal is constant. The following examples are conditions that are monitored: temperature, pressure, and level. The main display module measures the duty cycle of the output for the PWM sensor. The information is then sent to the quad gauge in order to be shown on one of the gauges. Note: See “Switch Input - Uncommitted” for input operation when the PWM sensor input is programmed to operate as a switch input. Use the Electrical System Schematic of the machine that is being serviced in order to determine the inputs that are programmed. Note: The input from the PWM sensor may be programmed to operate a gauge or an alarm indicator. The sensor can also be programmed to operate both a gauge and an alarm indicator.

Sensor Input - Frequency At each frequency sensor input (connector contacts 26, 30 and 36), an AC signal is present. The signal represents the speed of a machine system. Frequency sensors for engine speed and machine speed provide an AC signal to the main display module. The main display module measures the frequency (Hz) of the AC signals. The information is then sent to the speedometer/tachometer module.

At the input for the alternator terminal “R” (connector contact 30), the terminal “R” of the alternator provides an AC signal to the main display module. The main display module determines the speed of the alternator by measuring the frequency (Hz) of the AC signal. The alternator R terminal helps determine the condition of the electrical charging system. Harness wiring directly connects the alternator terminal “R” to the sensor input for the alternator “R”. The information on the alternator terminal “R” is used with other inputs (engine oil pressure, engine speed, etc) in order to determine when the engine is running.

Sender Input - 0- 240 Ohm Each 0-240 ohm sender input (connector contacts 9 and 18) may be programmed in order to operate as either a sender input or a switch input. A sender input measures a resistance value in order to determine the condition of the system. A resistive fuel level sender (or a component with a similar output signal) provides this information. The output resistance of the fuel level sender corresponds to the depth of fuel within the tank. The main display module measures the resistance value. The information is then sent to the quad gauge in order to be shown on one of the gauges. Note: See “Switch Input - Uncommitted” for input operation when the 0-240 ohm sender input is programmed to operate as a switch input. Use the Electrical System Schematic of the machine that is being serviced in order to determine the inputs that are programmed. Note: The 0-240 ohm sender input may be programmed to operate a gauge or an alarm indicator. The sensor can also be programmed to operate both a gauge and an alarm indicator.

Sender Input - 70-800 Ohm Each 70-800 ohm sender input (connector contacts 8, 10, 28 and 38) may be programmed in order to operate as a sender input, a PWM sensor input or a switch input. The 70-800 ohm sender input measures a resistance value in order to read the condition of the system. The temperature sender (or a component with a similar output signal) provides this information. The output resistance of the temperature sender corresponds to the temperature of the fluid that is being measured. Oil, coolant and hydraulic temperature are examples of fluid temperatures that are measured. The main display module measures the resistance value. The information is then sent to the quad gauge in order to be shown on one of the gauges.


Note: The 70-800 ohm sender input may be programmed to operate a gauge or an alarm indicator. The sensor can also be programmed to operate both a gauge and an alarm indicator.

Outputs

Note: See “Sensor Inputs - PWM” for input operation when the 70-800 ohm sender input is programmed to operate as a PWM sensor input. Use the Electrical System Schematic of the machine that is being serviced in order to determine the inputs that are programmed. Note: See “Switch Input - Uncommitted” for input operation when the 70-800 ohm sender input is programmed to operate as a switch input. Use the Electrical System Schematic of the machine that is being serviced in order to determine the inputs that are programmed.

Input - Voltage The input for battery voltage (connector contact 1 and 2) provides the main display module with power. The voltage input is also used by the main display module to monitor the machine electrical system. This information from the voltage helps determine the condition of the electrical system. When an alert indicator is used in order to indicate the voltage of the machine system, the battery signal is combined with the signal for the terminal “R” within the main display module. When an electrical system fault occurs, there are two possible warning categories. The category is set by the type of fault. Category 1 – The frequency for the terminal “R” from the alternator is less than 90 Hz or the system voltage is greater than 29.5 volts for at least 2 seconds. The system voltage is less than 24.8 volts for a least 2 seconds. Category 3 – The system voltage is less than 23.0 volts for at least 2 seconds or the system voltage is greater than 32.0 volts for at least 2 seconds.

Illustration 36

g00297407

Main Display Module (1) Alert Indicators. (2) Display area.

The outputs of the Caterpillar Monitoring System notify the operator of the status of the machine systems. The main display module provides electrical power for the other display modules and the sensors. The following outputs are on the Caterpillar Monitoring System: the display for the main display module, the display data link, the alert indicators, the action lamp, the action alarm, the sensor power supply, and the power supply for the main display module. The outputs on the main display module are the alert indicators (1) and the display area (2). The alert indicators notify the operator of abnormal conditions with the machine. The main display module uses the status of the uncommitted switch inputs, sender inputs and/or sensor inputs in order to determine when an abnormal condition is present. The main display module then FLASHES the appropriate alert indicator. The symbol of the FLASHING alert indicator identifies the responsible machine system. When an alert indicator FLASHES, an abnormal condition exists. For more information, see System Operation, “Warning Operation”. Note: The main display module may use a combination of inputs in order to determine abnormal conditions. For example, engine oil pressure and engine rpm may be used to enable the alert indicator for the machine electrical system. The alert indicator for the machine electrical system will FLASH if an abnormal condition exists on the input for the terminal “R” or the input for +battery.


The display area has various symbols that show the condition of the machine systems. The symbols also show information for service and setup. The type of information that is shown on the display depends on the operating mode. For more information about the display area, see System Operation, “Modes of Operation”.

Table 10

Contact Description Of Display Components Connector No.

Function

Type

1

+9 DCV

Input

2

Ground

Ground

Action Lamp

3

Display Clock

Input

When a serious abnormal condition exists, the main display module activates the output for the action lamp (connector contact 13) and the action lamp FLASHES. For more information, see System Operation, “Warning Operation”.

4

Display Data

Input

5

Display Load

Input

6

Harness Code

Open(1)

Action Alarm When a critical abnormal condition exists, the main display module activates the output for the action alarm (connector contact 4) and the action alarm SOUNDS. For more information, see System Operation, “Warning Operation”.

Power Supply Output - Sensor The output for the sensor power supply (connector contact 24) provides 8 DCV for the PWM sensors that are connected to the inputs of the main display module.

(1)

Used to give two display components of the same type a unique component number. This is needed so the main display module can send unique information to each identical component. Since all monitoring system configurations included in this manual have at most one module, this input should be open.

The display components receive information from the main display module. The information that is shown notifies the operator and the service person of the status of the machine systems. The components are the quad gauge module and the speedometer/tachometer module. i01858071

Quad Gauge Module SMCS Code: 7450

Power Supply Output - Display Modules The output for the power supply to the display module (connector contact 34) provides 9 DCV for the display modules. The quad gauge module and the speedometer/tachometer module cannot function without this power output. i01521112

Display Components SMCS Code: 7450 The following table shows the contact description for all the display components.

Illustration 37 An Example Of A Quad Gauge Module (1) Gauge warning area. (2) Pictograph symbol.

g00789595


The quad gauge module shows the following information: engine coolant temperature, articulation angle, system voltage, and fuel level. The main display module uses the information from sensor inputs or the CAT data link in order to calculate the values that are shown on the gauges. Pictograph symbol (2) identifies the parameter for the machine system which is shown on each gauge. Abnormal values are shown by the gauge warning area (1).

Note: The input is received from the fuel level sender. The warning level for this gauge is a Level I. i01020517

Speedometer/Tachometer Module SMCS Code: 7450

Table 11

Engine Coolant Temperature Gauge Minimum Displayed Value

40 °C (104 °F)

Midpoint Value

82 °C (179 °F)

Red Zone Value

107 °C (224 °F)

Maximum Displayed Value

140 °C (284 °F)

Note: The information is received from the engine coolant temperature sensor. The warning level for this gauge is a Level II. Illustration 38

Table 12

g00357114

Speedometer/Tachometer module

Articulation Angle Sensor Gauge Minimum Displayed Value

−20 °C (−4 °F)

Midpoint Value

0 °C (32 °F)


20 °C (68 °F)

Note: The information is received from the articulation angle sensor. Table 13

System Voltage Gauge Minimum Displayed Value

22 V

Midpoint Value

26.2 V

Red Zone Low

23.8 V

Red Zone High

28.5 V


31 V

Note: The information is received via the CAT data link. Table 14

(1) Tachometer. (2) Pictograph symbol. (3) Speed readout. (4) Gear readout.

Speed readout (3) consists of three digits and the readout may show the machine ground speed in MPH (km/h). The main display module calculates speed by using the information from a frequency sensor input or the CAT data link. Illumination of the appropriate digits shows the speed. Gear readout (4) consists of two digits that show the transmission gear which is engaged. The left digit shows the actual gear, “1”, “2”, “3”, etc. The right digit shows the direction that is selected, “F”, “N” or “R”. Tachometer (1) shows the engine speed in RPM. The engine speed is determined by the information that is sent to the main display module over the CAT data link. The engine speed is also determined from a frequency sensor input. i01858111

Switches SMCS Code: 1435; 7332

Fuel Level Gauge Minimum Displayed Value

5%

Midpoint Value

50%

Red Zone Value

10%


95%

Switches provide information (input) to the main display module. Switches are two state devices. The two states of the switches are open and closed. Closed – The switch connects the control input to frame ground.


Open – The switch connects the control input to nothing. (The input is floating.)

Pressure Switch (RH Brake System)

During normal operation, all the switches are closed to ground. When a condition exceeds the trip point of the switch, the switch opens. This tells the main display module of the abnormal condition. The main display module then begins the warning operation and the module notifies the operator of the abnormal condition (problem). Note: For specifications on the switches, see the Electrical System Schematic for that particular machine.

Rocker Switch (Operator Mode Selector) Grounding the operator mode selector switch causes the main display module to scroll through the available operator modes for the machine. Opening the selector switch places the Caterpillar Monitoring System in the currently displayed operator mode. A list of possible operator modes is shown at the beginning of the Modes of Operation section. See the Operation And Maintenance Manual in order to determine the “Operator Modes” that are available for the machine that is being serviced.

Temperature Switch (Hydraulic Oil)

Illustration 40

g00793486

Pressure Switch (1) Schematic symbol (2) Switch

During normal operation, pressure switch (2) is open to ground. The switch closes when brake system air pressure is present. The switch opens when brake system air pressure is too low. i01802612

Senders SMCS Code: 1408-UN

Level Sender (Fuel)

Illustration 39

g00304432

Temperature Switch (Hydraulic Oil) (1) Switch. (2) Schematic symbol.

During normal operation, temperature switch (1) is closed to ground. The switch opens when the temperature of the fluid system is greater than the specified value. The open switch tells the main display module that there is a high temperature. The switch is closed when the switch is off the machine.

Pressure Switch Pressure Switch (Parking Brake) Pressure Switch (LH Brake System)

Illustration 41

g00303717

Level Sender (Fuel) (1) Sender (2) Schematic symbol

Fuel level sender (1) provides fuel level sensing. A resistive signal which corresponds to the depth of fuel within the fuel tank is sent from the sender to the main display module. Typically, there are two possible types of senders: 0 to 90 ohms and 33 to 240 ohms. The main display module measures the resistance value in order to determine the fuel that is remaining in the tank. Typical gauge readings for the fuel level:


• When the fuel tank is at 4% of capacity, the gauge shows that the tank is empty.

Position Sender (Articulation Angle)

• When the fuel tank is at 14% of capacity, the gauge shows the needle at the red zone on the gauge.

• When the fuel tank is at 95% of capacity, the gauge shows that the tank is full.

Temperature Sender

Illustration 43

g00793324

Position Sender (Articulation Angle) (1) Schematic symbol (2) Sender

Illustration 42

g00303718

Temperature Sender (1) Schematic symbol (2) Sender

Temperature sender (2) provides a method for sensing fluid temperature. The temperature sender produces a resistive signal which corresponds to the temperature of the fluid that is being monitored. Typically, the resistance range of the sender is from 70 ohms at 110°C (230°F) to 3000 ohms at 25°C (77°F). The main display module measures the resistance value in order to determine the fluid temperature.

Position sender (2) provides articulation sensing. A resistive signal which corresponds to the articulation angle is sent from the sender to the main display module. The main display module measures the resistance value in order to determine the articulation angle. i01060965

Sensors SMCS Code: 1408-NS

General Information Sensors provide information (input) to the main display module about changing conditions. The sensor signal changes in a proportional manner in order to reflect the changing condition. The main display module shows the information from the sensors on the gauges. The main display module recognizes two types of sensor signals. Frequency – The sensor produces an AC signal. The frequency (Hz) varies as the condition changes. Pulse Width Modulated (PWM) – The sensor produces a digital signal. The duty cycle varies as the condition changes. The frequency of this signal is constant.

Frequency Sensors Frequency sensors produce an AC signal. The frequency (Hz) varies as the condition changes.


Pulse Width Modulated (PWM) Sensors

Speed Sensor

Illustration 44

g00304924

Speed Sensor (1) Sensor. (2) Schematic symbol.

Speed sensor (1) is a frequency sensor. Speed sensors are used in order to measure engine speed (RPM) and machine speed (MPH (km/h)). The sensor generates an AC signal from the passing gear teeth. The signal is sent to the main display module. The main display module measures the sensor frequency (one pulse per gear tooth). The main display module determines the engine speed or the machine speed. The speed is then shown on the display. The engine speed sensor is located on the flywheel housing. The speed sensor for the machine is located at the output end of the transmission housing.

Illustration 45

g00304925

Pulse Width Modulated Signal

Illustration 46

g00304926

Typical PWM Sensor Schematic

Pulse width modulated (PWM) sensors produce a digital signal. The duty cycle varies as the condition changes. The frequency remains constant.


Temperature Sensor

i01679184

Action Lamp SMCS Code: 1408-LMP; 7400-LMP

Illustration 49

g00304970

Action Lamp Symbol Illustration 47

g00304927

Temperature Sensor (1) Schematic symbol. (2) Sensor.

Temperature sensor (2) reacts to the temperature of fluids. Examples of the fluids are hydraulic oil, power train oil, and engine coolant. The sensor receives operating power from the main display module (8 DCV) or from the battery (24 DCV). The sensor sends the main display module a PWM signal. The signal changes as the fluid temperature changes. The main display module measures the duty cycle of the sensor signal in order to determine the fluid temperature.

Pressure Sensor

Illustration 48

The action lamp connects to an output of the main display module. The action lamp is an LED that is located within the operator’s viewing area. The FLASHING of the action lamp tells the operator that a condition exists. The condition will require changing the operation of the machine. The action lamp is located on the main display module. The action lamp will FLASH whenever a warning category 2, a warning category “2S”, or a warning category 3 problem exists. i01940097

Action Alarm SMCS Code: 7407

g00304929

Pressure Sensor

Illustration 50

(1) Schematic symbol. (2) Sensor.

Action Alarm

g00307223

(1) Schematic symbol. (2) Action alarm.

Pressure sensor (2) reacts to the pressure of fluids. The sensor receives operating power from the main display module (8 DCV) or from the battery (24 DCV). The sensor sends the main display module a PWM signal. The signal changes as the fluid pressure changes. The main display module measures the duty cycle of the sensor signal in order to determine the fluid pressure.

The action alarm connects to an output of the main display module. When the action alarm is audible, the machine needs immediate attention. A safe machine shutdown is required. The main display module will sound the action alarm whenever a warning category 3 problem exists. An alarm for a warning category 3 is a pulsating sound. The alarm for a warning category 2S is a continuous tone.


The action alarm does not operate when the engine is stopped. The main display module uses functions in order to determine when the engine is running. The following functions are examples: engine oil pressure, alternator speed, and engine speed. If necessary, the action alarm SOUNDS when the main display module decides that the engine is running. i00703569

Related Components SMCS Code: 1408; 7450

Alternator The R terminal of the alternator is connected to an input of the main display module. The main display module monitors the frequency at the R terminal of the alternator. This tells the main display module if the alternator is rotating.

Other Electronic Controls Some machines have electronic control modules that communicate with the main display module. The CAT data link connects these electronic controls together. This connection allows the sharing of information. The following information is an example of the information that is shared: engine oil pressure, harness codes, and diagnostic information. For example, an electronic engine control sends the engine speed information to the main display module over the CAT data link. In this situation, the engine speed sensor is not a Caterpillar Monitoring System component. If there is a problem with the engine speed sensor, the electronic engine control service manual would be used to troubleshoot the speed sensor circuit.

38 Troubleshooting Section

Troubleshooting Section Introduction

i01966052

Service Tools SMCS Code: 0785

i01400224

General Information

The following service tools should be used to aid in troubleshooting the electrical system. Table 15

Service Tools

SMCS Code: 7490 Part Number

Troubleshooting the Caterpillar Monitoring System requires additional information from the machine’s Service Manual. The additional manuals that may be required are the Service Manual, the System Schematic, the Parts Manual and the Operation and Maintenance Manual for the machine that is being serviced. As a guide, a typical system schematic is included at the end of this manual. For an accurate representation of the machine that is being diagnosed, refer to Electrical System Schematic in the Service Manual for the machine that is being serviced. When the troubleshooting procedure instructs you to “REPAIR THE HARNESS”, use the Electrical System Schematic for the machine that is being serviced to trace the circuit. Perform continuity checks at the harness connectors in order to locate harness failures. At the connectors of the components, always check the ground circuit. Less than five ohms of resistance is required between the ground contacts of the connector and the frame ground. Excessive ground resistance that is greater than five ohms can cause incorrect diagnosing of problems. During troubleshooting, inspect all connections before any component is replaced. If these connections are not clean and tight, permanent electrical problems or intermittent electrical problems can result. Check that the wires are pushed into the connectors completely. Make sure that the connections are tight before other tests are made. Failure of an electrical component can cause the failure of other components. Also, failure of an electrical component can be caused by the failure of other components. Always attempt to correct the cause of an electrical system failure before you replace a component.

Part CAT Electronic Technician

6V-7070 9U-7330

Digital Multimeter

8T-3224

Needle Tip Group

7X-1710

Multimeter Probe Group

8T-8726

Adapter Cable Assembly

6V-3000

Connector Repair Kit (Sure Seal)

9U-7246

Connector Repair Kit (Deutsch DT)

4C-3406

Connector Repair Kit (Deutsch)

4C-8195

Control Service Tool (Switch Box)

Illustration 51

g00280782

Connections for the Electronic Technician (ET) The components that are needed in order to use the CAT Electronic Technician in order to determine diagnostic codes are listed: (1) An IBM-COMPATIBLE personal computer with an installed current version of Caterpillar Electronic Technician software (2) 139-4166 Data Link Cable or 7X-1570 Data Link Cable (3) 7X-1425 Cable and 4C-6805 Adapter (4) Special Publication, JEBD3003, Special Publication, JERD2124, Special Publication, JERD2129 ; Caterpillar Electronic Technician software (5) 7X-1700 Communication Adapter Tool with Special Publication, NEXG4323, “Communications Adapter Software”


The Electronic Technician (ET) is used to communicate to the electronic control module over the data link by connecting to the machine diagnostic connector. For more information and the locations of the connectors, see Troubleshooting, “Electrical Components and Connector Locations” and the Electrical System Schematic in your machine’s Service Manual. For instructions on servicing Sure Seal connectors, see Special Instruction, SMHS7531. For instructions on servicing Deutsch DT connectors, see Special Instruction, SEHS9615.

Illustration 52

g00774942

Connections for the Communication Adapter II and the Electronic Technician (ET) The components that are needed in order to use the Communication Adapter II and the CAT Electronic Technician in order to determine diagnostic codes are listed: (6) (7) (8) (9)

Cable 171-4400 Communication Adapter II Service diagnostic cable. Current version of Caterpillar Electronic Technician software and an IBM-COMPATIBLE personal computer

Reference: See Special Publication, NEHS0758, “Communications Adapter II User’s Manual Contains Software”. Note: Caterpillar Electronic Technician (ET) is a software program that can be used on an IBM compatible personal computer. In order to use the Caterpillar Electronic Technician (ET), order the following materials: Special Publication, JERD2124, “ET Single Use Program License”, Special Publication, JEHP1026, “Information and Requirements Sheet”, 7X-1425 Data Link Cable and the Data Subscription, and Special Publication, JERD2142, “Data Subscription”. The Special Publication, JEHP1026, “Information and Requirements Sheet” lists the required hardware and the features of the ET. The Electronic Technician (ET) is not required in order to determine the diagnostic codes and the ET is not required in order to clear the diagnostic codes. However, the process of determining the diagnostic codes is easier and faster by using the ET. The ET can also display information on the history of a diagnostic code and the parameter status of diagnostic codes. These features allow the ET to be a useful tool for troubleshooting.

Use the digital multimeter for making continuity checks or for measuring voltage. For instructions about the use of the 6V-7070 Digital Multimeter, see Special Instruction, SEHS7734. The 7X-1710 Multimeter Probe measures the voltage at the connectors without disconnecting the connectors. The probe cables are pushed into the back of the connector along the wire. The 8T-8726 Adapter Cable has a 3 pin breakout connector. The adapter cable is used for measurements in the sensor circuits. Note: Except for harness tests, using continuity testers such as the 8T-0500 Continuity Tester or voltage testers such as the 5P-7277 Voltage Tester is not recommended for today’s Caterpillar electrical circuits.

Service Switches During troubleshooting, it is necessary for the service person to use the diagnostic operations of Caterpillar Monitoring System. Service personnel use the service switches in order to access the different display modes of diagnostic operation. The switches are the momentary type of switch. The service personnel activate the switches by pressing and holding. Pressing the clear switch grounds the clear input (contact 33) of the monitor. Pressing the set switch grounds the service switch (contact 23) of the monitor. The location of the service switches will vary depending on the machine that is being serviced. Not all machines are equipped with service switches. For a more accurate location of the service switches, see the Electrical System Schematic in the Service Manual for the machine.


4C-8195 Control Service Tool

Changing Modes Table 16

Activation Of Display Operations (Quick Reference) Display Operation

Service Contact(1)

Clear Contact(1)

To Scroll

Ground

Ground

To Hold

Open

Open

To Scroll

Ground

Open

To Hold

Open(2)

Open

Open

Ground

Open

Ground

Changing Modes:

Service Modes:

Illustration 53

g00743610

To

4C-8195 Control Service Tool

Clear(3)

Tattletale Mode: To Clear

Numeric Readout Mode:

(1) (2) (3)

Illustration 54

g00743652

To Scroll

Ground

Open

To Hold

Open

Open

of the service connector. Open when the desired information is shown during scrolling. A diagnostic code can be cleared only while it is on hold. The diagnostic code for a fault that is currently present can not be cleared

For a detailed explanation of the different modes, see Systems Operation, “Modes of Operation”.

Schematic for the Control Service Tool

The 4C-8195 Control Service Tool is used on machines that are not equipped with service switches. The 4C-8195 Control Service Tool is helpful for the service person to make the proper electrical connections at the service connector during troubleshooting. Three connectors are wired in parallel so that the service tool is usable on the different types of machine harnesses. Actuating the mode switch scrolls through the display modes. Actuating the scroll switch will scroll through the display while the main display module is in the service mode or the numeric readout mode. Actuating the clear switch clears the diagnostic code that is being continuously shown when the main display module is in service mode. Actuating the clear switch clears all extreme values when the main display module is in tattletale mode.

i01398954

Electrical Component and Connector Locations SMCS Code: 7553-546-WW

General Information The Electrical System Schematic, Parts Manual and Operation and Maintenance Manual for the machine that is being serviced should be used to locate electrical components and connectors. The following information is a guide to reading the tables on the back of the Electrical System Schematic.

• The “Component Location” table uses white circles to mark the locations in the profile of the machine and in the area views. Alphabetical letters in the “Machine Location” column indicate a general area of the machine. Refer to the corresponding footnote at the end of the table for a description of the location.


• The “Harness Connector Location” table uses

white circles to mark the locations in the general view and in the area views. Alphabetical letters in the “Machine Location” column indicate a general area of the machine. Refer to the corresponding footnote at the end of the table for a description of the location.

Note: The “Harness Connector Location” table uses black circles on certain electrical system schematics.

Connector Contact Numbers for the Main Display Module Illustration 56

g00309224

Service connector with jumpers (typical example) (1) Jumper. Service contact grounded (2) Jumper. Clear contact grounded (3) Service connector.

Illustration 57

g00309227

End view of service connectors

Illustration 55

g00309228

Connector of the main display module

Service Connector The service connector provides access to the service and clear inputs of the main display module. Connector contact 1 is the service input and contact 2 is the clear input. Contacts 3 and 4 could be any wire from the 200 family. The service connector is usually located under the dashboard within the operator compartment. The service connector is a DT type of connector. For a more accurate location of the service connector, see the Electrical System Schematic in the Service Manual.

Various diagnostic functions require the grounding and/or the opening of the service and clear contacts at the service connector. During troubleshooting, it is necessary for the service person to make the proper electrical connections between the contacts of the service connector. These electrical connections are made with two jumpers. See Troubleshooting, “Accessing Diagnostic Information”.


i01671837

Diagnostic Capabilities SMCS Code: 7490

The Caterpillar Electronic Technician (ET)

g00777826

Illustration 58

The Caterpillar Electronic Technician (ET) is a software program that is used to access data. The service technician can use the Caterpillar Electronic Technician in order to perform maintenance work on the machine. Some of the options that are available with the Caterpillar Electronic Technician are listed below:

• View Diagnostic codes. See Troubleshooting,

“Using the Caterpillar Electronic Technician to Determine Diagnostic Codes”.

• View the status of parameters. • Clear active diagnostic codes and clear logged diagnostic codes

• Perform calibration of machine systems.

• Program the ECM (Flash). This is done with the “WINflash” program. See Testing and Adjusting, “Electronic Control Module (ECM) - Flash Program”.

• Print reports. The following list contains some of the diagnostic functions and programming functions that are performed by the service tools.

• The failures of the ECM system are displayed. • The status of most of the inputs and the outputs are displayed.

• The settings for the ECM are displayed. • Display the status of the input and output parameters in real time.


• Display the clock hour of the internal diagnostic clock.

• The number of occurrences and the clock hour

of the first occurrence and the last occurrence is displayed for each logged diagnostic code.

• The definition for each logged diagnostic code and each event is displayed.

• Load new FLASH software. See Troubleshooting, “Diagnostic Code List” for the list of diagnostic codes for the ECM. See Troubleshooting, “Using the Caterpillar Electronic Technician to Determine Diagnostic Codes”. Diagnostic information is accessed with the following drop down menus:

• Active diagnostic codes • Logged diagnostic codes Status Groups For The Electronic Technician The Status groups are lists of machine parameters. The status of the parameters are shown in real time.

Illustration 59 Typical ET Status Screen

g00867289


Diagnostic Code Procedures

(Table 17, contd)

Diagnostic Codes For Caterpillar Monitoring System (MID 030)(1) CID/FMI i01663522

Diagnostic Code List SMCS Code: 7569

(1)

Table 17

Diagnostic Codes For Caterpillar Monitoring System (MID 030)(1) Description

CID/FMI

CID 0084 Speed Sensor (Ground): FMI 08

Signal is abnormal

CID 0096 Level Sender (Fuel): FMI 03

Signal voltage above normal or short to +battery

FMI 04

Voltage below normal or short to ground

FMI 08

Signal is abnormal

CID 0248 Data Link: FMI 02

Data erratic, intermittent, or incorrect

CID 0263 Sensor Power Supply: FMI 03


FMI 04


CID 0271 Alarm (Action): FMI 03


FMI 05

Current below normal or open circuit

FMI 06

Current above normal or short to ground

CID 0324 Lamp (Action): FMI 03


FMI 05

Current below normal or open circuit

FMI 06

Current above normal or short to ground

Description

FMI 03


FMI 04


This table pertains only to faults with a MID of 030.

Note: Every machine may not have all of the diagnostic codes that are listed in the preceding table. Also, every machine may not have all the FMI for a given CID. Note: The preceding table shows the diagnostic codes for the Caterpillar Monitoring System. When the Caterpillar Monitoring System is in the service mode, diagnostic codes from the other electronic control modules are shown on the display area of the Caterpillar Monitoring System. The information from the diagnostic code is transferred from other electronic control modules via the CAT data link to the main display module. This diagnostic information is shown when the main display module is in the service mode. The module identifier (MID) indicates the electronic control module that is sending the diagnostic code. The MID for the Caterpillar Monitoring System is “030”. This Service Manual is used for diagnostic codes with a MID of “030”. The MID of other electronic control modules on a particular machine are listed on the Electrical System Schematic. Troubleshooting information for those diagnostic codes can be found in the service manual for that system. Note: When a sensor fault is present, the corresponding warning for that sensor is also activated for the operator. For example, if the signal wire for the engine coolant temperature sensor is shorted to the +battery circuit, then the following actions take place:

• The corresponding diagnostic code is stored in memory.

• The gauge for the engine coolant temperature is indicating in the warning region.

CID 0615 Position Sender (Articulation) FMI 03


• The action lamp is FLASHING.

FMI 04


Notice that the second and third above items are the same warning indications that are activated if the engine overheats.

CID 0819 Display Data Link: FMI 02

Data erratic, intermittent, or incorrect

CID 0821 Display Power Supply: (continued)


i01672648

Using Caterpillar Monitoring System to Determine Diagnostic Codes SMCS Code: 7490; 7569

Procedure

Note: The diagnostic scrolling mode may be entered in order to see the diagnostic codes, but the diagnostic codes can be more easily diagnosed by using the service mode. The service mode allows the diagnostic codes to be placed on hold for further investigation. The service mode allows the diagnostic codes to be cleared when the problem has been fixed. 2. The diagnostic code is shown and the diagnostic code is on hold at this time. The display toggles between showing MID (3) and CID (5) and FMI (6). If you are in the service mode and a diagnostic code is not present, “---” will be displayed. 3. In order to view all the diagnostic codes, scroll through the diagnostic codes. In order to scroll through the diagnostic codes, close the service switch. The display momentarily shows MID (3), CID (5) and FMI (6) for each diagnostic code. The word “End” will be shown after the last diagnostic code in the list. 4. Place the desired diagnostic code on hold. In order to place the diagnostic code on hold, open the service switch when the desired diagnostic code is shown.

Illustration 60

g00429460

Display Area (1) First display. (2) Second display. (3) Module identifier (MID). (4) service code indicator (“SERV CODE”). (5) Component identifier (CID). (6) Failure mode identifier (FMI).

The following procedures may cause new diagnostic codes to be logged. Therefore, before any procedures are performed make a list of all the active diagnostic codes in order to determine the system problems. Clear the diagnostic codes that were caused by the procedure, when each procedure is complete. Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped. Use the following procedure to troubleshoot diagnostic code information. 1. Place the Caterpillar Monitoring System in service mode (mode 3). In order to place the Caterpillar Monitoring System in service mode, close the service and clear switches. Open the switches when service mode “3” is shown on the display.

5. Use the information from the MID in order to determine the ECM that is generating the diagnostic code. If the MID is not 027, see Electrical System Schematic, “Module Identifier (MID) Table” of the machine that is being serviced. Use the table to determine the ECM that has detected the diagnostic code. Then see the service manual module for that electronic control. If the MID is 082, use this Service Manual Module to troubleshoot the diagnostic code that generated the diagnostic code. 6. Observe the “SERV CODE” indicator (4). In the service mode, the “SERV CODE” indicator functions as a “SERV CODE” indicator.

• If the “SERV CODE” indicator (4) shows

“SERV CODE”, then the failure that caused the diagnostic code that is shown is currently present.

• If the “SERV CODE” indicator (4) is OFF, then

the diagnostic code that caused the diagnostic code that is shown is not present at this time.

7. See the corresponding test in order to troubleshoot the diagnostic code. Use the Service Manual for the ECM that is generating the diagnostic code. 8. After a diagnostic code is corrected, clear the diagnostic code. In order to clear the diagnostic code, close the clear switch while the diagnostic code is on hold. After clearing, the display advances to the next available diagnostic code.


9. Repeat Steps 2 through 8 for the remaining diagnostic codes. Return to the normal mode when you are finished. In order to return to the normal mode, close the service and clear switches. Open the switches when mode “0” is shown on the display. i01782268

Using Caterpillar Electronic Technician to Determine Diagnostic Codes SMCS Code: 0785-UE; 7569 Connect the Caterpillar ET to the machine. Turn the key switch to the RUN position. Start the Cat ET. The Cat ET will initiate communications with the Electronic Control Modules on the machine. After communication has been established, the Cat ET will list the Electronic Control Modules. Choose the desired Electronic Control Module. After the diagnostic codes have been determined with the Cat ET, see the test procedure for the corresponding diagnostic code. Reference: Troubleshooting, “Service Tools” Active Diagnostic Codes


Illustration 61 Typical Cat ET screen for active diagnostic codes

The following procedures may cause new diagnostic codes to be logged. Therefore, before any procedures are performed make a list of all the active diagnostic codes in order to determine the system problems. Clear the diagnostic codes that were caused by the procedure, when each procedure is complete. Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped. A screen is provided in Cat ET for active diagnostic codes. The screen will display the diagnostic codes that are active. Active diagnostic information shall include a component identifier (CID), a failure mode identifier (FMI) and a text description of the problem. Logged Diagnostic Codes

g00859671


g00859762

Illustration 62 Typical Cat ET screen for logged diagnostic codes

A screen is provided in Cat ET for logged diagnostic codes. The screen will display diagnostic codes that are logged. The Cat ET will log diagnostic codes that are intermittent. The logged diagnostic data shall include a component identifier (CID), a failure mode identifier (FMI), and a text description of the problem. Also, the logged diagnostic data shall include the number of occurrences of the problem and two time stamps. The time stamp displays the first occurrence of the problem and the time stamp displays the most recent occurrence of the problem.

i01802609

MID 030 - CID 0084 - FMI 08 SMCS Code: 7493-038 Conditions Which Generate This Code:

Diagnostics are logged in non-volatile memory. On powerup, the ECM will clear any diagnostic codes that have not been detected or active within the last 150 hours of machine operation.

Illustration 63 Schematic for the ground speed sensor

g00866484


This diagnostic code is associated with the ground speed sensor. The FMI 08 means that the main display module has determined that the signal frequency or the signal pulse width is not within the expected range. The possible causes of this diagnostic code are listed below:

• The sensor has failed.

B. Disconnect the J1 machine harness connector from the main display module. C. The sensor remains disconnected. D. At the machine harness connector for the sensor, measure the resistance from the signal contact 3 (wire C913-BU) and ground contact 2 (wire 210-BK).

• Mechanical devices are loose.

E. At the machine harness connector for the sensor, measure the resistance from the signal contact 3 (wire C913-BU) and + battery contact 1 (wire 113-OR).

• The main display module has failed. This is

Expected Result:

• Intermittent connections or poor connections

unlikely.

Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0084 FMI 08 is active before performing this procedure. Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.

Test Step 1. CHECK THE SENSOR. A. Turn the key start switch and the disconnect switch to the OFF position. B. Disconnect the sensor from the machine harness. C. At the harness connector for the sensor, measure the resistance between signal contact 3 (wire C913-BU) and ground contact 2 (wire 210-BK). Expected Result: The resistance that is measured is greater than 5000 ohms. Results:

• YES – The resistance that is measured is greater than 5000 ohms. The resistance is correct. Proceed to test step 2.

• NO – The resistance that is measured is less than

The resistance that is measured is greater than 5000 ohms. Results:

• YES – The resistance that is measured is greater than 5000 ohms. The resistance of the harness is correct. Proceed to test step 3.

• NO – The resistance measures less than 5000 ohms. The machine harness has failed.

Repair: There is a short between the signal contact J1-26 and the circuit with the low resistance measurement. Repair the harness or replace the harness. STOP.

Test Step 3. CHECK FOR AN OPEN IN THE SIGNAL CIRCUIT. A. The sensor and the main display module remain disconnected from the machine harness. B. The key start switch and the disconnect switch remain in the OFF position. C. Measure the resistance of the signal circuit from contact J1-26 (wire C913-BU) to contact 3 (wire C913-BU) of the sensor. Expected Result:

5000 ohms. The sensor has failed.

The resistance measures less than 5 ohms.

Repair: Replace the sensor.

Results:

STOP.

• YES – The resistance measures less than 5 ohms.

Test Step 2. CHECK THE WIRING HARNESS. A. The key start switch and the disconnect switch remain in the OFF position.

The signal circuit is correct. The diagnostic code may be caused by an intermittent failure in the machine harness.


Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”.

Test Step 1. CHECK THE CONTROL AND THE HARNESS.

STOP.

B. Disconnect the machine harness connector from the fuel level sender.

• NO – The resistance is greater than 5000 ohms. Repair: The signal circuit has failed. There is an open in the signal circuit of the machine harness. Repair the machine harness or replace the machine harness.

A. Turn the disconnect switch and the key start switch to the ON position.

C. At the machine harness connector for the sender, measure the voltage (DCV) between the signal contact 1 (wire 447-PK) and the return contact 2 (wire 201-BK). Expected Result:

STOP.

The voltage is between 4.5 and 8.0 DCV. i01678169

MID 030 - CID 0096 - FMI 03

Results:

• OK – The voltage is between 4.5 and 8.0 DCV. The

SMCS Code: 1273-038-UN

main display module and the harness are correct.

Conditions Which Generate This Code:

Repair: Replace the sender. STOP.

• NOT OK – The voltage is not between 4.5 and 8.0 DCV. The main display module or the harness has failed. Proceed to Test Step 2.

Illustration 64

g00866238

Test Step 2. CHECK THE RETURN CIRCUIT OF THE HARNESS.

Schematic for the fuel level sender

A. The sender remains disconnected.

This diagnostic code is recorded when the main display module reads the signal voltage of the fuel level sender and the voltage is too high. The possible causes of this diagnostic code are listed here:

B. Turn the disconnect switch and the key start switch to the OFF position.

• The sender has failed. • The return circuit of the sender is open in the machine harness.

• The signal circuit in the machine harness is shorted to a source of positive voltage.

• The signal circuit in the machine harness is open or the sender is disconnected.

• The main display module has failed. This is unlikely.

System Response: This failure causes the fuel gauge to always indicate an empty fuel tank or the fuel gauge may intermittently indicate an empty fuel tank.

C. Disconnect the J1 machine harness connector from the main display module. D. Measure the resistance of the return circuit between contact 2 (wire 201-BK) of the machine harness for the sender and contact J1-2 of the machine harness for the main control module. Expected Result: The resistance is less than 5.0 ohms. Results:

• OK – The resistance is less than 5.0 ohms. The

harness resistance is correct. Proceed to Test Step 3.

• NOT OK – The resistance is greater than 5.0

ohms. The ground circuit in the harness has failed. There is an open circuit between the ground contact and frame ground.


Repair: Repair the machine harness or replace the machine harness. STOP.

Test Step 3. CHECK FOR A SHORTED HARNESS

i01678452

MID 030 - CID 0096 - FMI 04 SMCS Code: 1273-038-UN Conditions Which Generate This Code:

A. The sender and the main display module remain disconnected from the machine harness. B. The disconnect switch and the key start switch remain in the OFF position. C. At the machine harness connector for the sender, measure the resistance between the signal contact 1 (wire 447-PK) and the +battery circuit at the contact J1-1 of the machine harness connector for the main display module.

Illustration 65

g00866238

Schematic for the fuel level sender

Expected Result:

This diagnostic code is recorded when the main display module reads the signal voltage of the fuel level sender and the voltage is too low.

The resistance is greater than 5000 ohms.

The possible causes of this failure are listed here:

Results:

• The sender has failed.

• OK – The resistance is greater than 5000 ohms.

• The signal circuit in the machine harness is shorted

The main display module has failed.

Repair: It is unlikely that an ECM has failed. Exit this procedure. Perform this CID 0096 FMI 03 procedure again. If the failure is not found, replace the main display module. Refer to the Testing and Adjusting, “Module - Replace”. STOP.

• NOT OK – The resistance is less than 5000 ohms.

to ground.

• The main display module has failed. This is unlikely.

This failure causes the fuel gauge to always indicate an empty fuel tank or the fuel gauge may intermittently indicate an empty fuel tank.

Test Step 1. CHECK THE SENDER.

The machine harness has failed. There is a short between the +battery circuit and the signal circuit in the machine harness.

A. Disconnect the machine harness from the sender.

Repair: Repair the machine harness or replace the machine harness.

The diagnostic code changes from CID 0096 FMI 04 to CID 0096 FMI 03.

STOP.

Results:

Expected Result:

• OK – The diagnostic code changed from CID 0096 FMI 04 to CID 0096 FMI 03. This indicates that the failure is no longer present. The sender has failed. Repair: Replace the sender. STOP.

• NOT OK – The diagnostic code remains. The

failure remains present. The sender is not causing the failure. Proceed to test step 2.

Test Step 2. CHECK THE HARNESS. A. The sender remains disconnected from the machine harness.


B. Turn the disconnect switch and the key start switch to the OFF position. C. Disconnect the J1 machine harness connector from the main display module. D. At the machine harness connector for the sender, measure the resistance between the signal contact 1 (wire 447-PK) and frame ground. Expected Result:

Service Notes: Ensure that the desired code (CID and FMI) is on hold. Ensure that the diagnostic code indicator shows “SERV CODE”. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced. Note: See Troubleshooting, “Sensor Signal Voltage” in order to troubleshoot this component.


Perform the following diagnostic procedure: “Sensor Signal Voltage ”

Results:

Results:


• OK – STOP.

The harness circuit resistance is correct. The main display module has failed. Repair: It is unlikely that the ECM has failed. Exit this procedure, and perform this procedure again. If the failure is not found, replace the ECM. See Testing and Adjusting, “ Module - Replace”.

• REPAIRED, OK – STOP. i01858627

MID 030 - CID 0248 - FMI 02 SMCS Code: 7490-038

STOP.



The machine harness has failed. There is a short between frame ground and the signal circuit in the machine harness.


Illustration 67

g00530708

Schematic for the Caterpillar data link i01916153


This diagnostic code is recorded when the main display module does not receive expected information. The following example shows a possible diagnostic code. The information from the actual gear status is not being received from other electronic control modules through the CAT data link. The information from the CAT data link indicates the abnormal values in the readout. The possible causes of this diagnostic code are listed below. The causes are listed in order of probability:

• Poor electrical connection at a machine harness connector

Illustration 66 Schematic for the fuel level sender

g00866238

• The circuit for the CAT data link in the machine harness is shorted to ground.

• The circuit for the CAT data link in the machine harness is shorted to the +battery.

• The circuit for the CAT data link in the machine harness is open.


Note: An electronic control module which uses the CAT data link may have lost power or an electronic control may have failed. This is unlikely. If the main display module was recently replaced, see Testing and Adjusting, “Main Display Module Initialization Adjust”. Service Notes: Ensure that the desired diagnostic code (CID and FMI) is on hold. Ensure that the service code indicator shows “SERV CODE”.

Test Step 1. CHECK FOR OTHER CODES. A. Check other electronic control modules for a similar diagnostic code. If a similar diagnostic code is found, exit this test. Perform the corresponding procedures for the other diagnostic codes that are shown. Expected Result: There are other diagnostic codes that are showing. Results:

• YES – Exit this procedure and perform the other procedures for the diagnostic codes that are shown. STOP.

• NO – There are not any other diagnostic codes that are shown. Proceed to test step 2.

Test Step 2. INSPECT THE HARNESS CONNECTORS. A. Turn the disconnect switch to the OFF position. B. Inspect the connections for the machine harness that are related to the CAT data link. C. Make sure that connectors are clean and tight. Expected Result: The machine harness is correct. Results:

•

OK – The machine harness is correct. Proceed to test step 3.

• NOT OK – The machine harness is not correct. Repair: Repair the machine harness or replace the machine harness. STOP.

B. Disconnect the machine harness from all the electronic control modules that use the CAT data link. C. At the machine harness connector for the main display module, measure the resistance between frame ground and the CAT data link circuits (contacts 5 and 14). Expected Result: The resistance that is measured is less than 5000 ohms. Results:

• YES – The resistance is less than 5000 ohms.

The machine harness has failed. There is a short between the frame ground and the CAT data link circuit in the machine harness. Repair: Repair the machine harness or replace the machine harness. STOP.

• NO – The resistance is greater than 5000 ohms.

The harness circuit resistance is correct. Proceed to test step 4.

Test Step 4. CHECK FOR A SHORT TO THE +BATTERY. A. The disconnect switch remains OFF. B. All related control modules remain disconnected from the machine harness. C. At the machine harness connector for the main display module, measure the resistance between the +battery (contact 1) and the CAT data link circuits (contacts 5 and 14). Expected Result: The resistance is greater than 5000 ohms. Results:


The harness circuit resistance is correct. Proceed to test step 5.

• NOT OK – The resistance is less than 5000 ohms. The machine harness has failed. There is a short between the +battery and the CAT data link circuit in the machine harness.

Test Step 3. CHECK FOR A SHORT TO GROUND.


A. The disconnect switch remains OFF.

STOP.


Test Step 5. CHECK FOR AN OPEN HARNESS. A. The disconnect switch remains OFF. B. All related control modules remain disconnected from the machine harness.

i01440228

MID 030 - CID 0263 - FMI 03 SMCS Code: 7490-038-NS Conditions Which Generate This Code:

C. Check the continuity of the CAT data link circuit in the machine harness. D. Measure the resistance from the connector of the main display module (contact 5 and 14) to the connector for each of the related electronic control modules. Illustration 68

g00754378

Expected Result:

Schematic for the sensor power supply

The resistance is less than 5 ohms.

This diagnostic code is recorded when the main display module reads an above normal sensor supply voltage (+24 DCV).

Results:

• YES – The resistance is less than 5 ohms. The CAT data link circuit in the machine harness is correct.

Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• NO – The resistance is greater than 5 ohms. The machine harness has failed. The CAT data link circuit is open in the machine harness.


Note: The procedures that are used to troubleshoot this diagnostic code may cause additional diagnostic codes to be logged. Find the cause and repair the cause of this diagnostic code before you troubleshoot any new diagnostic codes.

Test Step 1. CHECK THE VOLTAGE AT THE MAIN DISPLAY MODULE. A. Use the 7X-1710 Multimeter Probe in order to check the voltage at the connector for the main display module. Measure the voltage from the contact 1 to the contact 2 (ground). DO NOT disconnect the harness from the module. Expected Result: The supply voltage that is measured is 24.0 ± 0.5 DCV. Results:

• YES – The voltage is 24.0 ± 0.5 DCV. The sensor

supply voltage is correct. Verify that the diagnostic code is still present. If the diagnostic code is still present the main display module has failed. Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the module. See Testing and Adjusting, “Module - Replace”. STOP.


• NO – The voltage is NOT 24.0 ± 0.5 DCV. The

sensor supply voltage is NOT correct. Proceed to test step 2.

Test Step 2. CHECK THE HARNESS FOR A SHORT TO THE +BATTERY CIRCUIT. A. Disconnect the machine harness from the main display module. B. At the machine harness connector for the main display module, measure the voltage from the connector contact 1 to 2 (ground).

Repair: Replace the sensor. STOP.

• NO – The voltage is NOT approximately 0 DCV. The harness or a sensor has failed. Repeat this test. The machine harness is shorted to the +battery circuit if all the sensors have been disconnected from the machine harness and the voltage is NOT approximately 0 DCV.

Repair: Repair the harness or replace the harness. STOP.

Expected Result: The voltage that is measured should be approximately 0 DCV.

i01440283

MID 030 - CID 0263 - FMI 04

Results:

SMCS Code: 7490-038-NS

• YES – The voltage is approximately 0 DCV. The


voltage is correct.

Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the module. See Testing and Adjusting, “Module - Replace”. STOP.

Illustration 69

g00754378

Schematic for the sensor power supply

• NO – The voltage is NOT approximately 0 DCV.

This diagnostic code is recorded when the main display module reads the signal voltage. The voltage from the sensor is too low.

Test Step 3. DISCONNECT THE SENSORS.

Test Step 1. CHECK THE VOLTAGE AT THE MAIN DISPLAY.

A. Disconnect one of the sensors that are connected to the +24 DCV sensor supply of the main display module from the machine harness.

A. Use the 7X-1710 Multimeter Probe in order to check the voltage at the connector for the main display module. Measure the voltage from contact 1 to contact 2 (ground). DO NOT disconnect the harness from the module.

The harness or a sensor has failed. Proceed to test step 3.

B. After you disconnect the sensor, measure the voltage from the connector contact 2 (ground) to contact 1 of the machine harness connector for the main display module. Expected Result: The voltage that is measured should be approximately 0 DCV. Results:

• YES – The voltage is approximately 0 DCV.

The voltage is correct. The sensor that was just disconnected has failed.

Expected Result: The voltage measures 24.0 ± 0.5 DCV. Results:

• YES – The voltage is 24.0 ± 0.5 DCV. The sensor

supply voltage is correct. Verify that the diagnostic code exists.



• NO – The voltage is NOT 24.0 ± 0.5 DCV. The

sensor supply voltage is NOT correct. Proceed to test step 2.

Test Step 2. DISCONNECT THE SENSORS. A. Continue to monitor the sensor supply voltage. B. Disconnect one of the sensors that are connected to the +24 DCV sensor supply of the main display module from the machine harness. C. After you disconnect the sensor, check the voltage reading on the multimeter. Expected Result:

Expected Result: The resistance that is measured is greater than 5000 ohms. Results:

• YES – The resistance is greater than 5000 ohms.

The harness circuit resistance is correct. The main display module has failed. Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• NO – The resistance is less than 5000 ohms. The machine harness has failed. There is a short to ground in the machine harness.


The voltage that is measured is 24.0 ± 0.5 DCV. Results:

• YES – The voltage is 24.0 ± 0.5 DCV. The

sensor supply is correct. The sensor that was just disconnected has failed. Repair: Replace the sensor.

i01394484


STOP.

• NO – The voltage is NOT 24.0 ± 0.5 DCV. Repeat

this test step for the remaining sensors. If the voltage is NOT correct after the remaining sensors are disconnected and tested. Continue to the next test step. Proceed to test step 3.

Test Step 3. CHECK FOR A SHORT TO GROUND. A. Turn the disconnect switch and the key start switch to the OFF position. B. The sensors remain disconnected. C. Disconnect the machine harness from the main display module. D. At the machine harness connector for the main display module, measure the resistance between the frame ground and the sensor supply circuit (connector contact 1).

Illustration 70

g00544121

Schematic for the alarm (action)

This diagnostic code is recorded when the main display module reads the voltage of the circuit for the action alarm as above normal. The result of this diagnostic code is the continuous sounding of the action alarm. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.


CHECK THE ALARM CIRCUIT.

C. Turn the disconnect switch to the ON position.

This diagnostic code is recorded when the main display module reads the current of the action alarm. The current for the action alarm is below normal. The action alarm does not SOUND as a result of this diagnostic code. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

D. Listen for the SOUNDING of the action alarm.

Test Step 1. CHECK THE ALARM.

E. Turn the key start switch to the ON position.

A. Disconnect the machine harness from the alarm.

Expected Result:

B. At the machine harness connector for the alarm, place a jumper across the two contacts.

A. Turn the disconnect switch and the key start switch to the OFF position. B. Disconnect the machine harness from the main display module.

The alarm is sounding.

Expected Result:

Results:

• YES – The alarm is SOUNDING. The harness

The CID 0271 FMI 05 is still present.

circuit 410-WH is shorted to the +battery.

Results:

Repair: Repair the harness or replace the harness.

• YES – The CID 0271 FMI 05 remains present. The

STOP.

• NO – The alarm does NOT SOUND. The main display module has failed.

Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”.

action alarm is not causing the diagnostic code. Verify that the action alarm is correct. The correct resistance for a good alarm is 200 ± 100 ohms. Proceed to test step 2.

• NO – The CID 0271 FMI 05 is NO longer present. The alarm is open.

Repair: Replace the action alarm. Verify that the action alarm is open. The correct resistance for a good alarm is 200 ±100 ohms. STOP.

Test Step 2. CHECK THE HARNESS.

STOP. i01394545


A. Turn the disconnect switch and the key start switch to the OFF position. B. Remove the jumper from the connector of the alarm and reconnect the alarm to the machine harness. C. Disconnect the machine harness from the main display module. D. At the machine harness connector for the module, measure the resistance between contact 4 (410-WH) and frame ground. Expected Result:

Illustration 71 Schematic for the alarm (action)

g00544121

The resistance is greater than 300 ohms. Results:


The harness circuit is open. Proceed to test step 3.


• NOT OK – The resistance is less than 300 ohms. The harness circuit resistance is correct. Proceed to test step 4.

Test Step 3. CHECK THE HARNESS. A. Disconnect the machine harness from the alarm. B. Check for an open in the circuit 410-WH. Check between the harness connector for the main display module (contact 4) and the harness connector for the action alarm (contact 1). C. Check for an open in the circuit 201-BK. Check between the harness connector for the action alarm (contact 2) and the frame ground.

• NO – The diagnostic code is NO longer active.

The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP. i01394618


Expected Result: The machine harness is correct. Results:

• OK – The machine harness is correct. STOP. • NOT OK – The machine harness is not correct. Repair: Repair the machine harness or replace the machine harness. STOP.

Test Step 4. CHECK THE MAIN DISPLAY MODULE. A. Reconnect the machine harness connector to the main display module. B. Reconnect the alarm to the machine harness.

Illustration 72

g00544121

Schematic for the alarm (action)

This diagnostic code is recorded when the main display module reads the voltage of the circuit for the action alarm as above normal. The action alarm does not SOUND as a result of this diagnostic code. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Test Step 1. CHECK THE ALARM. A. Disconnect the machine harness from the alarm.

C. Turn the disconnect switch and the key start switch to the ON position.

Expected Result:

Expected Result:

The CID 0271 FMI 06 remains present.

The CID 0271 FMI 05 is still present.

Results:

Results:

• OK – The diagnostic code remains present. The

• YES – The CID 0271 FMI 05 remains present. The main display module has failed.


action alarm is not causing the diagnostic code. Proceed to test step 2.

• NOT OK – The diagnostic code is NO longer

present. The correct resistance for a good alarm is 200 ± 100 ohms. The alarm has failed. Repair: Replace the action alarm. STOP.


Test Step 2. CHECK THE HARNESS. A. Turn the disconnect switch to the OFF position. B. The alarm remains disconnected from the machine harness. C. Disconnect the machine harness from the main display module.


active. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP. i01394739

D. At the machine harness connector for the main display module, measure the resistance between contact 4 (410-WH) and frame ground.

MID 030 - CID 0324 - FMI 03

Expected Result:


SMCS Code: 7431-038-LMP



The harness resistance is correct. Proceed to test step 3.


Illustration 73

g00544436

The harness has failed.

Schematic for the lamp (action)


This diagnostic code is recorded when the main display module reads the voltage of the circuit for the action lamp as above normal. The action lamp is ON CONTINUOUSLY as a result of this diagnostic code. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

STOP.

Test Step 3. CHECK THE MODULE. A. Remove contact 4 from the machine harness connector for the main display module by using the correct service tools. B. Reconnect the machine harness connector to the module. C. Turn the disconnect switch and the key start switch to the ON position.

CHECK THE LAMP CIRCUIT. A. Turn the disconnect switch and the key start switch to the OFF position. B. Disconnect the machine harness from the main display module.

D. Place the same diagnostic code on hold and check the service code indicator.

C. Turn the disconnect switch to the ON position.

Expected Result:

D. Observe the action lamp.

The CID 0271 FMI 06 is present.

E. Turn the key start switch to the ON position.

Results:

Expected Result:

• OK – The CID 0271 FMI 06 remains present. The

The action lamp is ON.

main display module has failed.

Repair: It is unlikely that the module has failed. Exit this procedure and perform this diagnostic code procedure again. If the problem has not been found, then replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

Results:

• OK – The action lamp is ON. The harness circuit 411-PK is shorted to the +battery.



• NOT OK – The action lamp is OFF. The module has failed.

Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP. i01394817

MID 030 - CID 0324 - FMI 05 SMCS Code: 7431-038-LMP Conditions Which Generate This Code:

• NOT OK – The CID 0324 FMI 05 is present. The action lamp is not causing the diagnostic code. Proceed to test step 2.

Test Step 2. CHECK THE HARNESS. A. Turn the disconnect switch and the key start switch to the OFF position. B. Remove the jumper from wire 411-PK to frame ground. Make sure that the action lamp is connected to the machine harness. C. Disconnect the machine harness from the main display module. D. At the machine harness connector for the main display module, measure the resistance between contact 13 (411-PK) and frame ground. Expected Result: The resistance is greater than 100 ohms. Results:


The harness circuit is open. Proceed to test step 3.

Illustration 74

g00544436

Schematic for the action lamp

This diagnostic code is recorded when the main display module reads the current of the circuit for the action lamp and the current is below normal. The action lamp does not light as a result of this diagnostic code. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Test Step 1. CHECK THE LAMP. A. At the action lamp, use a jumper to connect wire 411-PK to frame ground. Expected Result: The CID 0324 FMI 05 is no longer present. Results:

• OK – The CID 0324 FMI 05 is no longer present. The lamp or the lamp socket is open.

Repair: Replace the action lamp. NOTE: For the purposes of this test, the correct resistance for a lamp is less than 200 ohms. STOP.

• NOT OK – The resistance is less than 100 ohms. The harness circuit resistance is correct. Replace the main display module.


Test Step 3. CHECK THE HARNESS. A. At the action lamp, disconnect wire 411-PK from the lamp socket. B. Check for an open in the circuit 411-PK. Check between contact 13 of the harness connector for the main display module and the lamp socket. C. Check for an open in the circuit 201-BK. Check between the lamp socket and the frame ground. Expected Result: The circuits are correct.


Results:

Test Step 2. CHECK THE HARNESS.

• OK – The circuits are correct. STOP.

A. Turn the disconnect switch to the OFF position.

• NOT OK – The circuits are NOT correct.

B. Wire 411-PK remains disconnected from the action lamp.

Repair: Repair the harness or replace the harness. STOP. i01394886

MID 030 - CID 0324 - FMI 06

C. Disconnect the machine harness from the main display module. D. At the machine harness connector for the main display module, measure the resistance between contact 13 (411-PK) and frame ground.

SMCS Code: 7431-038-LMP

Expected Result:




The harness resistance is correct. Proceed to test step 3.

• NOT OK – The resistance is less than 5000 ohms. Illustration 75

g00544436

Schematic for the action lamp

The harness has failed.


This diagnostic code is recorded when the main display module reads the voltage of the circuit for the action lamp and the current is above normal. The action lamp does not light as a result of this diagnostic code. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Test Step 3. CHECK THE MAIN DISPLAY MODULE.

Test Step 1. CHECK THE LAMP.

B. Reconnect the harness connector to the main display module.

A. At the action lamp, disconnect wire 411-PK from the lamp socket.

C. Turn the disconnect switch and the key start switches to the ON position.

Expected Result:

D. Place the same diagnostic code on hold. Check the service code indicator.

The CID 0324 FMI 06 is present. Results:

• OK – The CID 0324 FMI 06 is present. The action lamp is not causing the diagnostic code. Proceed to test step 2.

• NOT OK – The CID 0324 FMI 06 is NO longer

present. The lamp or the lamp socket has failed. The correct resistance for a lamp is greater than 10 ohms. Repair: Replace the action lamp. STOP.

STOP.

A. Remove contact 13 from the machine harness connector for the main display module.

Expected Result: The CID 0324 FMI 06 is present. Results:

• OK – The CID 0324 FMI 06 remains present. The main display module has failed.



i01528712


STOP.


active. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP. i01441628

MID 030 - CID 0601 - FMI 08 SMCS Code: 4250-038-NS Conditions Which Generate This Code:

Illustration 77

g00793582

Schematic for the articulation position sender

This diagnostic code is recorded when the main display module reads the signal voltage. The voltage from the sender is too high. The articulation angle gauge on the Caterpillar Monitoring System does not work when this diagnostic code is active. The following causes could signal this diagnostic code:

• The sender has failed. • The ground circuit for the sender in the machine harness is shorted to +battery.

• The signal circuit in the machine harness is shorted to +battery.

Illustration 76

g00528295

Schematic for the pressure sensor (brake air)

Service Notes: Ensure that the desired diagnostic code is on hold. Ensure that the diagnostic code indicator shows “SERV CODE”. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and the wire numbers by using the Electrical System Schematic for the machine that is being serviced. Note: See Diagnostic Function, “Sensor Signal Voltage” in order to troubleshoot this component. Perform the following diagnostic procedure: “Sensor Signal Voltage” Results:

• OK – STOP. • REPAIRED, OK – STOP.

• The signal circuit in the machine harness is open or the sender is disconnected.

• The main display module has failed. Service Notes: Ensure that the desired diagnostic code (CID and FMI) is on hold. Ensure that the diagnostic code indicator shows “SERV CODE”. The schematic that is shown above represents a typical installation of the component. Verify the connector and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Test Step 1. CHECK THE MAIN DISPLAY MODULE AND THE HARNESS. A. Turn the disconnect switch and the key start switch to the ON position. B. The diagnostic code indicator should show “SERV CODE” for the diagnostic code. C. Disconnect the machine harness from the sender that is causing the diagnostic code. D. Connect the signal wire A429-PK to the ground wire 201-BK on the machine harness connector.


E. Observe the diagnostic code indicator.

Results:

Expected Result:

• 6.0 ± 0.5 DCV – The voltage is 6.0 ± 0.5 DCV. The

The diagnostic code indicator remains ON. Results:

• YES – The diagnostic code indicator remains ON.

The harness wiring or the main display module has failed. Proceed to test step 2.

• NO – The diagnostic code indicator turns OFF. The sender has failed.

Repair: Replace the sender. STOP.

Test Step 2. CHECK FOR AN OPEN GROUND. A. Remove the jumper wire between the signal wire A429-PK and the ground wire 201-BK. B. Turn the disconnect switch and the key start switch to the OFF position. C. Measure the resistance between frame ground and the ground wire for the sender. Expected Result: The resistance is 5 ohms or less. Results:

• YES – The resistance is 5 ohms or less. Proceed

voltage is correct. Verify that the diagnostic code is still present.


• LESS THAN 0.5 DCV – The voltage is less than 0.5 DCV. The harness wiring has failed. There is an open circuit or a short to ground in the signal wire for the sender.

Repair: Repair the harness or replace the harness. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. It is unlikely that the main display module has failed. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• NOT 6.0 BUT ABOVE 0.5 DCV – The voltage is

less than 0.5 DCV. The harness wiring has failed. There is an open circuit or a short to ground in the signal wire for the sender.

Repair: Repair the ground wire or replace the ground wire for the sender.

Repair: Repair the harness or replace the harness. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. It is unlikely that the main display module has failed. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”.

STOP.

STOP.

to test step 3.

• NO – The resistance is greater than 5 ohms. The ground wire for the harness is open.

Test Step 3. CHECK THE SIGNAL WIRE FOR THE SENDER. A. Turn the disconnect switch and the key start switch to the ON position. B. Measure the voltage between the frame ground and the signal wire for the sender. Expected Result: The voltage measurement should be within one of the following specifications.


i01528825

Expected Result:

MID 030 - CID 0615 - FMI 04

The diagnostic code indicator is ON.

SMCS Code: 4806-038-UN

Results:


• YES – The diagnostic code indicator stays ON.

The harness wiring or the main display module has failed. Proceed to test step 2.

• NO – The diagnostic code indicator turns OFF. The sender has failed.

Repair: Replace the sender. Illustration 78

g00793582

Schematic for the articulation position sender

This diagnostic code is recorded when the main display module reads a low sender signal. When this diagnostic code occurs, the gauge indicates an abnormally high value. The following symptoms could cause the diagnostic code:

•

The sender has failed.

• The signal circuit in the machine harness is shorted to ground.

• The main display module has failed. Note: The main display module is unable to determine when a sender is open. Also, the main display module is unable to determine when a sender signal harness is open. This condition is recognized when the gauge constantly indicates a value at the far left side of the scale.

STOP.

Test Step 2. CHECK THE SIGNAL WIRE FOR A SHORT TO GROUND. A. The disconnect switch and the key start switch remain in the ON position. B. At the machine harness for the sender, measure the voltage between the frame ground and the sender signal wire. Expected Result: The voltage that is measured is within one of the following specifications. Results:

• 6.0 ± 0.5 DCV – The voltage is 6.0 ± 0.5 DCV. The voltage is correct. Verify that the diagnostic code remains.

Service Notes: Ensure that the desired diagnostic code is on hold. Ensure that the diagnostic code indicator shows “SERV CODE”. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.


Test Step 1. CHECK THE MAIN DISPLAY MODULE AND THE HARNESS.

STOP.

A. Turn the disconnect switch and the key start switch to the ON position. B. The diagnostic code indicator should show “SERV CODE”. C. Disconnect the machine harness from the sender that is causing the diagnostic code. D. Observe the diagnostic code indicator.

• LESS THAN 0.5 DCV – The voltage is less than 0.5 DCV. The harness wiring has failed. There is an open circuit or a short to ground in the signal wire for the sensor.


Repair: Repair the harness or replace the harness. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. It is unlikely that the main display module has failed. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• NOT 6.0 BUT ABOVE 0.5 DCV – The voltage is

less than 0.5 DCV. The harness wiring has failed. There is an open circuit or a short to ground in the signal wire for the sensor. Repair: Repair the harness or replace the harness. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. It is unlikely that the main display module has failed. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP. i01944181


Illustration 79 Schematic for the display power supply

g00737908


This diagnostic code is recorded when the main display module does not receive expected information. When the main display module sends information to a display component, the display component sends a signal back to the main display module. The signal confirms correct information. When the main display module does not receive expected information, the diagnostic code is logged. As a result of this diagnostic code, the main display module may not respond to the information that is received. Gauges and readouts could be incorrect when the main display module is in normal mode. Check the connections for the display data link. Check for opens or shorts in the harness wiring for the display data link.

Test Step 1. INSPECT THE HARNESS CONNECTIONS. A. Turn the disconnect switch to the OFF position. B. Inspect the harness connections that are related to the display data link. Make sure that the connectors are clean and tight. C. Check the mating of the harness connectors. D. Check wires at the connector. E. Check each wire for nicks or signs of abrasion in the insulation. F. Check for moisture at the connector. G. Check for dirty contacts or corroded contacts. H. Check each pin and each socket. Expected Result: The machine harness connectors are tight and free of corrosion. Results:

B. Disconnect the harness from the main display module. C. Disconnect the machine harness connectors from all of the display components. D. At the harness connectors for the main display module, measure the resistance between the contacts that are listed below:

• Connector contact 1 (wire 113-OR) and the Display Data Link circuit contact 4 (wire C413-YL).

• Connector contact 1 (wire 113-OR) and the Display Data Link circuit contact 5 (wire C414-BU).

• Connector contact 1 (wire 113-OR) and

the Display Data Link circuit contact 3 (wire E708-PK).

Expected Result: The resistance is greater than 5000 ohms. Results:

• OK – The resistance is greater than 5000 ohms. Proceed to test step 3.

• NOT OK – The resistance is less than 5 ohms. The machine harness has failed.

Repair: There is a short between the +battery and the circuits of the display data link in the machine harness. Replace the machine harness or repair the machine harness. STOP.

Test Step 3. CHECK FOR AN OPEN HARNESS.

• OK – The machine harness connectors are tight

A. The disconnect switch and the key start switch remain in the OFF position.

•

B. All the display modules remain disconnected from the machine harness.

and free of corrosion. Proceed to test step 2.

NOT OK – The machine harness connectors are NOT tight and free of corrosion. Repair: Repair the machine harness or replace the machine harness. STOP.

Test Step 2. CHECK FOR A SHORT TO +BATTERY. A. Turn the key start switch and the disconnect switch to the OFF position.

C. Measure the resistance of the circuits of the display data link that are listed below:

• Measure the resistance between connector

contact 35 (wire C413-YL) to connector contact 4 (wire C413-YL) of the message center module.



contact 15 (wire C414-BU) to connector contact 5 (wire C414-BU) of the message center module.


contact 25 (wire E708-PK) to connector contact 3 (wire E708-PK) of the message center module.

Expected Result: The resistance is less than 5 ohms. Results:

• OK – The resistance is less than 5 ohms. The

circuit resistance is correct. Proceed to test step 4.

• – The resistance is greater than 5000 ohms. Repair: There is an open in the machine harness. Repair the machine harness or Replace the machine harness. STOP.

Test Step 4. CHECK FOR A SHORT TO GROUND A. The disconnect switch and the key start switch remain in the OFF position. B. The main display module and all the display components remain disconnected from the machine harness. C. At the machine harness connector for the main display module, measure the resistance between frame ground and the connector contacts 35 (wire C413-YL), 15 (wire C414-BU) and 25(wire E708-PK) of the display data link. Expected Result: The resistance is greater than 5000 ohms. Results:

• OK – The resistance is greater than 5000 ohms. The resistance of the circuit is correct. Proceed to test step 5.

• NOT OK – The resistance is less than 5000 ohms. The resistance of the circuit is not correct.

Repair: There is a short between frame ground and the circuits of the display data link in the machine harness. Replace the machine harness or repair the machine harness. STOP.

Test Step 5. CHECK FOR + 12 DCV A. Reconnect all modules to the machine harness. B. Turn the disconnect switch and the key start switch to the ON position. C. Use the 7X-1710 Cable probes to check the voltage at the contact 1 (wire E707-GN) to contact 2 (wire 201-BK) of the message center module. Expected Result: The voltage is 9.0 ± 0.5 DCV. Results:

• OK – The voltage is 9.0 ± 0.5 DCV. Repair: Replace the message center module. STOP.

• NOT OK – The voltage is NOT 9.0 ± 0.5 DCV. The voltage is not correct.

Repair: The main display module has failed. It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. If the problem is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.


i01395272


g00737908


This diagnostic code is recorded when the main display module reads the voltage of the display power supply circuit and the voltage is above normal. Normal display power supply voltage is 9.0 ± 0.5 DCV. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Test Step 1. CHECK THE VOLTAGE AT THE MAIN DISPLAY MODULE. A. Use the 7X-1710 Multimeter Probe Group. Check the voltage at the connector for the main display module. Measure the voltage from the contact 34 to the contact 2 (ground). B. DO NOT disconnect the harness from the module. C. The correct voltage should measure 9.0 ± 0.5 DCV. Expected Result: The voltage that is measured is 9.0 ± 0.5 DCV.

Results:

• OK – The voltage is 9.0 ± 0.5 DCV. The display

power supply voltage is correct. Check the main display module for the same diagnostic code. If the service code indicator is still ON, the main display module has failed. Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• NOT OK – The voltage is NOT 9.0 ± 0.5 DCV.

The display power supply voltage is NOT correct. Proceed to test step 2.

Test Step 2. CHECK THE HARNESS FOR A SHORT TO +BATTERY. A. Disconnect the machine harness from the main display module.


B. At the machine harness connector for the main display module, measure the voltage from the connector contact 34 to 2 (ground). Expected Result: The voltage that is measured is 0.0 ± 0.5 DCV. Results:

• OK – The voltage is 0.0 ± 0.5 DCV. The voltage is correct. The main display module has failed.


• NOT OK – The voltage is NOT 0.0 ± 0.5 DCV. The harness has failed.

Repair: Repair the harness or replace the harness. STOP. i01487073



g00737908


This diagnostic code is recorded when the main display module reads the voltage of the display power supply circuit and the voltage is below normal. Normal display power supply voltage is 9.0 ± 0.5 DCV. The schematic that is shown above represents a typical installation of the component. Verify the connector contact and wire numbers by using the Electrical System Schematic for the machine that is being serviced.

Expected Result: The voltage that is measured is 9.0 ± 0.5 DCV. Results:

• OK – The voltage is 9.0 ± 0.5 DCV. The power

supply to the module is correct. The module that was just disconnected has failed.

Test Step 1. CHECK THE VOLTAGE AT THE MAIN DISPLAY MODULE.

Repair: Replace the module that was disconnected.

A. DO NOT disconnect the harness from the module.

STOP.

B. Use the 7X-1710 Multimeter Probe Group. Check the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2 (ground). Expected Result: The voltage measures 9.0 ± 0.5 DCV. Results:

• OK – The voltage is 9.0 ± 0.5 DCV. The display

power supply voltage is correct. Check the main display module for the same diagnostic code. If the service code indicator is still ON, the main display module has failed. Repair: It is unlikely that the main display module has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code indicator is illuminated for this diagnostic code. If the cause of the diagnostic code is not found, replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.


The display power supply voltage is NOT correct. Proceed to test step 2.

Test Step 2. DISCONNECT THE MODULES. A. Use the 7X-1710 Multimeter Probe Group. Check the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2 (ground). B. Disconnect a module from the machine harness one at a time. C. Continue to measure the voltage at the connector for the main display module. Measure the voltage from contact 34 to contact 2.


The display power supply voltage is not correct. Repeat this test step again. All the modules have been disconnected from the machine harness and the voltage is NOT 9.0 ± 0.5 DCV. Proceed to test step 3.

Test Step 3. CHECK FOR A SHORT TO GROUND. A. Turn the disconnect switch and the key start switch to the OFF position. B. Disconnect the machine harness from the main display module. C. At the machine harness connector for the main display module, measure the resistance. Measure the resistance between harness connector contact 34 and harness connector contact 2. Expected Result: The resistance that is measured is greater than 5000 ohms. Results:

• OK – The resistance is greater than 5000 ohms. STOP.

• NOT OK – The resistance is less than 5000 ohms. The harness has failed.



Diagnostic System Procedures

B. Place a jumper wire from the signal wire to the ground wire. (If a ground wire is not present, connect the signal wire to frame ground.) i01432657

Expected Result:

Alert Indicator Is Always Flashing

The alert indicator continues FLASHING.

SMCS Code: 7400-038-IND

• YES – The alert indicator continues FLASHING.

System Operation Description: This procedure is for the parameter that has the alert indicator which is FLASHING constantly. This condition is caused by an undesired open circuit or a failed main display module. The main display module is unable to identify system errors in simple circuits. No service code is available in order to assist the operator with troubleshooting. A possible problem exists when the operation of an alert indicator does not correspond to a known condition of the machine. For example, the alert indicator always FLASHES regardless of the actual pressure of the engine oil. Before you start troubleshooting, ensure that a diagnostic code exists. For a description of normal conditions that cause these events, see the Operation and Maintenance Manual for the machine that is being serviced. Perform the following procedures only if a fault is suspected. Note: The indicator reflects the open or grounded condition of the switch inputs. When a switch input is open, the corresponding alert indicator FLASHES. When a switch input is grounded, the corresponding alert indicator is OFF. Therefore, in order to check a circuit, the service person opens the switch. Then, the service person grounds the switch. This is done while the service person is watching for the correct result on the alert indicator.

Results: The machine harness is open or the main display module has failed. Proceed to test step 3.

• NO – The alert indicator stops FLASHING. The

circuit is operating correctly. The switch has failed. Repair: Check or replace the switch. STOP.

Test Step 3. CHECK THE HARNESS. A. Turn the disconnect switch and the key start switch to the OFF position. B. On the Electrical System Schematic, trace the signal wire from the switch to the main display module. C. Determine the signal contact (connector contact) of the machine harness at the main display module. D. Disconnect the machine harness from the main display module. E. At the machine harness connector for the main display, check for continuity between the signal contact and contact 2 or frame ground if a ground wire is not present at contact 2. (The jumper is in place from the previous test.)

Test Step 1. LOCATE THE SWITCH.

Expected Result:

A. Locate the switch which corresponds to the parameter that always FLASHES the alert indicator. (If necessary, use the Electrical System Schematic in order to assist in locating the switch.)

The resistance is greater than 5.0 ohms.

Expected Result: The appropriate switch is located. Results:

•

OK – The appropriate switch is located. Proceed to test step 2.

Test Step 2. CHECK THE HARNESS. A. Disconnect the signal wire from the switch.

Results:

• YES – The resistance is greater than 5 ohms. Repair: Repair the harness or replace the harness. STOP.

• NO – The resistance is less than 5 ohms. The harness is not causing the problem. The main display module has failed.



Expected Result: The alert indicator is FLASHING. Results:

• YES – The alert indicator FLASHES. The circuit is operating correctly. The switch has failed.

Repair: Repair the switch or replace the switch. i01432665

Alert Indicator Never Flashes SMCS Code: 7450-038-IND System Operation Description: The main display module is unable to identify system errors in simple circuits. No service code is available in order to assist the operator with troubleshooting. A possible failure exists when the operation of an alert indicator does not correspond to a known condition of the machine. For example, the alert indicator never FLASHES regardless of the actual pressure of the engine oil. Before you start troubleshooting, ensure that a problem exists. For a description of normal conditions that cause these events, see the Operation and Maintenance Manual for the machine that is being serviced. Perform the following procedures only if a failure is suspected. The indicator reflects the open or grounded condition of the switch inputs. When a switch input is open, the corresponding alert indicator FLASHES. When a switch input is grounded, the corresponding alert indicator is OFF. Therefore, in order to check a circuit, the service person opens the switch. Then, the service person grounds the switch. This is done while the service person is watching for the correct result on the alert indicator.

STOP.

• NO – The alert indicator does NOT FLASH. The circuit has failed. The signal wire is probably shorted to ground. Proceed to test step 3.

Test Step 3. CHECK THE HARNESS A. Turn the disconnect switch and the key start switch to the OFF position. B. The signal wire remains disconnected from the switch. Do not allow the signal wire to touch any objects. C. On the Electrical System Schematic, trace the signal wire from the switch to the main display module. D. Determine the signal contact (connector contact) of the machine harness at the main display module. E. Disconnect the machine harness from the main display module. F. At the machine harness connector for the display module, check for continuity between the signal contact and contact 2 or frame ground if a ground wire is not present at contact 2.

Test Step 1. LOCATE THE SWITCH

Expected Result:

A. Locate the switch for the alert indicator that never flashes. (If necessary, use the Electrical System Schematic to assist in locating the switch.)


Expected Result:

• YES – The resistance is greater than 5000 ohms.

The switch is located. Results:

• OK – The switch is located. Proceed to test step 2. Test Step 2. CHECK THE HARNESS. A. Disconnect the signal wire from the switch.

Results: The harness is not causing the failure. The main display module has failed.



• NO – The resistance is less than 5000 ohms.

The harness has failed. The signal wire within the harness is shorted to ground. Repair: Repair the harness or replace the harness. STOP. i01398181

Harness Code SMCS Code: 1408-038 S/N: ASD1-Up S/N: ARL1-Up S/N: APM1-Up S/N: APN1-Up System Operation Description: Table 18

Harness Code Troubleshooting(1) Main Display Module Connector Contact

31

3

12

22

16

6

Wire Identification

270-BK

271-BK

272-BK

273-BK

274-BK

275-BK

Harness Code Plug Contact(2)

1

2

3

4

5

6

Machine Code

Specified Status

01

O(3)

G(4)

G

G

G

G

02

G

O

G

G

G

G

03

O

O

G

G

G

G

04

G

G

O

G

G

G

05

O

G

O

G

G

G

06

G

O

O

G

G

G

07

O

O

O

G

G

G

08

G

G

G

O

G

G

09

O

G

G

O

G

G

10

G

O

G

O

G

G

11

O

O

G

O

G

G

12

G

G

O

O

G

G

13

O

G

O

O

G

G

14

G

O

O

O

G

G

15

O

O

O

O

G

G

16

G

G

G

G

O

G

17

O

G

G

G

O

G

18

G

O

G

G

O

G (continued)


(Table 18, contd)

Harness Code Troubleshooting(1) Main Display Module Connector Contact

31

3

12

22

16

6

19

O

O

G

G

O

G

20

G

G

O

G

O

G

21

O

G

O

G

O

G

22

G

O

O

G

O

G

23

O

O

O

G

O

G

24

G

G

G

O

O

G

25

O

G

G

O

O

G

26

G

O

G

O

O

G

27

O

O

G

O

O

G

28

G

G

O

O

O

G

29

O

G

O

O

O

G

30

G

O

O

O

O

G

31

O

O

O

O

O

G

32

G

G

G

G

G

O

33

O

G

G

G

G

O

34

G

O

G

G

G

O

35

O

O

G

G

G

O

36

G

G

O

G

G

O

37

O

G

O

G

G

O

38

G

O

O

G

G

O

39

O

O

O

G

G

O

40

G

G

G

O

G

O

41

O

G

G

O

G

O

42

G

O

G

O

G

O

43

O

O

G

O

G

O

44

G

G

O

O

G

O

45

O

G

O

O

G

O

46

G

O

O

O

G

O

47

O

O

O

O

G

O

48

G

G

G

G

O

O

49

O

G

G

G

O

O

50

G

O

G

G

O

O

51

O

O

G

G

O

O

52

G

G

O

G

O

O

53

O

G

O

G

O

O

54

G

O

O

G

O

O (continued)


(Table 18, contd)

Harness Code Troubleshooting(1)

(1) (2) (3) (4)

Main Display Module Connector Contact

31

3

12

22

16

6

55

O

O

O

G

O

O

56

G

G

G

O

O

O

57

O

G

G

O

O

O

58

G

O

G

O

O

O

59

O

O

G

O

O

O

60

G

G

O

O

O

O

61

O

G

O

O

O

O

62

G

O

O

O

O

O

Main display module is in the Harness Code Mode (Mode 1). For machines so equipped. For machines without a harness code plug, permanent harness code connections are in the machine harness. O = open G = grounded

Before you perform this procedure, determine the proper machine code. The main display module must have the correct part number for the particular machine. If the machine code is not shown correctly, this procedure determines the component that is malfunctioning. This failure could be caused by a failure in the main display module, a wrong harness code plug or a harness that has failed.

C. Check for continuity between the connector contacts that are grounded contacts and contact 2 (ground). Check for continuity at the machine harness connector for the main display module.

Note: The harness code and the machine code are similar terms. The codes describe the particular machine. The harness code is the status (open or ground) of the six harness code inputs (connector contacts 3, 6, 12, 16, 22 and 31). The main display module assigns a number to a machine. This number is the machine code. The machine code is shown during harness code mode. Each sales model has a specific harness code. Therefore, each sales model also has a specific machine code. The specific machine code is listed in Systems Operation, “Harness Code Mode”. The specific harness code is given in the Electrical System Schematic.

Results:

Note: The following procedure checks for incorrect harness codes on the inputs for the main display module. Compare the status of the harness code that is found in the test “Determine the machine code” to the status at the inputs for the main display module. The table identifies the connector contacts and wire identification of the harness code circuits. Contacts that are specified as grounded contacts should be checked for opens in the harness. Contacts that are specified as open contacts should be checked for shorts in the harness.

Test Step 1. CHECK FOR OPENS A. Turn the disconnect switch to the OFF position. B. Disconnect the machine harness from the main display module.

Expected Result: The resistance measures 5.0 Ohms or less.

• YES – The resistance is 5.0 Ohms or less. The

circuit for the harness code is not open. No defect was found in the ground circuits for the harness code. Proceed to test step 2.

• NO – The resistance is greater than 5.0 Ohms.

The circuit for the harness code is open. Check the harness code plug on so equipped machines. Record the open contact of the machine harness connector. Repair: Repair the open circuits for the harness code that is found or replace the machine harness. If conditions are not resolved, proceed to test step 2.

Test Step 2. CHECK FOR SHORTS A. The disconnect switch remains in the OFF position. The machine harness to the main display module remains disconnected. B. Measure the resistance between the connector contacts that are specified as open contacts and contact 2 (ground). Measure the resistance at the machine harness connector for the main display module.


Expected Result:

i01916278

The resistance measures 5000 Ohms or more.

Pulse Width Modulated Sensor

Results:


• YES – The resistance is 5000 Ohms or more.

System Operation Description:

The circuit for the harness code is not shorted to ground. No defect was found in the circuit for the harness code. STOP.

• NO – The resistance is less than 5000 Ohms.

The circuit for the harness code is shorted. Check the harness code plug on so equipped machines. Record the shorted contact of the machine harness connector. Repair: Repair the shorted circuits of the harness code that are found or replace the machine harness. If conditions are not resolved, proceed to test step 3.

Test Step 3. CHECK IF THE PROBLEM REMAINS A. Reconnect the harness connectors. B. Turn the disconnect switch and the key start switch to the ON position. C. Recheck the machine code. Expected Result: The main display module shows the correct machine code. Results:

• YES – The main display module shows the correct machine code. STOP.

• NO – The main display module does not show the correct machine code. Replace the module.

Repair: It is unlikely that the module has failed. Exit this procedure and perform this diagnostic code procedure again. If the problem has not been found, then replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

Illustration 82

g00315944

Schematic symbol for a typical pulse width modulated sensor (PWM)

Note: In addition to these tests, the Caterpillar Monitoring System diagnostics are helpful for troubleshooting sensors. Numeric readout mode shows a numeric value of the information from each sensor input. For a detailed explanation, refer to Systems Operation, “Numeric Readout Mode”. When you are testing a sensor, it is necessary to identify the connector contacts and the harness wires. The Electrical System Schematic shows the connector contact numbers and corresponding wire numbers. See the Electrical System Schematic in the Service Manual for the machine. On all machines, the wire numbers and connector contacts are identified by these general rules:

• The “+V” wire numbers are from 100 to 199. The “+V” contact corresponds to this wire number.

• The ground wire number is between 200 and

299. The ground contact corresponds to this wire number.

• The wire number for the signal circuits is from 400

to 499. The signal contact corresponds to this wire number.

For an example, see Illustration 82:

• The “+V” wire is wire number 113. • The “+V” contact is contact “A”. • The ground wire is wire number 201.


• The ground contact is contact “B”.

Repair: If the sensor and the harness are correct, it is likely that the main display module has failed. Replace the main display module. See Testing and Adjusting, “Module - Replace”.

• The signal wire is wire number 443. • The signal contact is contact “C”.

STOP.

Table 19

Tools Needed

i01916286

9U-7330

Multimeter

1

7X-1710

Multimeter Probe Group

1

Sensor Signal Voltage SMCS Code: 7490-038-NS

Test Step 1. TROUBLESHOOT THE SENSORS.

System Operation Description:

Troubleshoot sensor circuits in the following order.

Note: The main display module is connected.

A. Perform the Troubleshooting, “Sensor Signal Voltage” procedure. This procedure checks the sensor voltages at the sensor while the circuits remain connected. DISCONNECT NOTHING. Troubleshoot “as is” before disconnecting any circuits. Disconnecting circuits first may alter a poor connection. Proving the original cause of a problem may be difficult or impossible.

Table 20

Sensor Voltage Specifications For The Sensor Voltage Test 100-3055 Temperature Sensor And 131-0427 Temperature Sensor Temperature

Signal Voltage(1)

−20 to 0°C (−4 to 32°F)

1.1 to 1.4 DCV

11 to 15%

0 to 20°C (32 to 68°F)

1.4 to 2.0 DCV

15 to 23%

20 to 40°C (68 to 104°F)

2.0 to 3.1 DCV

23 to 37%

• OK – This test step has determined the cause of

40 to 60°C (104 to 140°F)

3.1 to 4.5 DCV

37 to 55%

60 to 80°C (140 to 176°F)

4.5 to 5.7 DCV

55 to 71%

• NOT OK – This test step has NOT determined the

80 to 100°C (176 to 212°F)

5.7 to 6.6 DCV

71 to 82%

100 to 120°C (212 to 248°F)

6.6 to 7.2 DCV

82 to 89%

120 to 140°C (248 to 275°F)

7.2 to 7.4 DCV

89 to 93%

Expected Result: The Troubleshooting, “Sensor Signal Voltage” procedure has determined the cause of the problem.

Duty Cycle

Results: the problem. STOP.

cause of the problem. Proceed to test step 2.

Test Step 2. TROUBLESHOOT THE SENSORS A. Perform the Troubleshooting, “Sensor Dynamic Operation” procedure. This is an additional test. This will test the sensor during actual operating conditions. Expected Result: The Troubleshooting, “Sensor Dynamic Operation” procedure has determined the cause of the problem. Results:

• OK – This test step has determined the cause of the problem. STOP.

• NOT OK – This test step has NOT determined the cause of the problem.

(1)

These voltages are guidelines for troubleshooting and are not considered exact. The tolerance is ± 10%, depending on the condition of the harness. Most important is that the output voltage changes smoothly as the temperature changes.


Results:

Table 21

Sensor Voltage Specifications For Sensor Voltage Test 3E-5370 Temperature Sensor Group And 131-0784 Temperature Sensor Temperature

Signal Voltage(1)

Duty Cycle

• YES – The voltage is between 7.5 and 8.5 DCV. The system voltage is present. Proceed to test step 2.

• NO – The voltage is not between 7.5 and 8.5 DCV.

−40 to 20°C (−40 to −4°F)

0.8 to 1.5 DCV

4 to 11%

There is an open circuit. Trace the +V and ground circuits in the machine harness.

−20 to 0°C (−4 to 32°F)

1.5 to 2.5 DCV

11 to 22%


0 to 20°C (32 to 68°F)

2.5 to 3.7 DCV

22 to 34%

STOP.

20 to 40°C (68 to 104°F)

3.7 to 4.8 DCV

34 to 46%

40 to 60°C (104 to 140°F)

4.8 to 6.0 DCV

46 to 59%

60 to 80°C (140 to 176°F)

6.0 to 7.2 DCV

59 to 71%

80 to 100°C (176 to 212°F)

7.2 to 8.1 DCV

71 to 81%

100 to 120°C (212 to 248°F)

8.1 to 8.8 DCV

81 to 87%

120 to 140°C (248 to 275°F)

8.8 to 9.2 DCV

87 to 92%

(1)

These voltages are guidelines for troubleshooting and are not considered exact. The tolerance is ± 10%, depending on the condition of the harness. Most important is that the output voltage changes smoothly as the temperature changes.

Locate the suspect sensor. Identify the sensor wires and connector contacts. See Troubleshooting, “Pulse Width Modulated (PWM) Sensor - Test”. DO NOT DISCONNECT ANY HARNESS CONNECTORS AT THIS TIME. Turn the key start switch to the ON position. DO NOT START THE ENGINE.

Test Step 1. CHECK THE SENSOR POWER. A. At the sensor connector, identify the +V and ground circuits.

Test Step 2. CHECK THE SIGNAL VOLTAGE. A. At the sensor connector, identify the signal and ground circuits. B. Push the 7X-1710 Cable Probes in the back of the sensor connector along side of the signal and the ground circuit wires. C. Measure the signal voltage and record the signal voltage. Note: If a precise signal voltage is necessary, use the specifications that are listed in the provided tables. Expected Result: The measured signal voltage is approximately between 1.0 and 7.0 DCV. The measured signal voltage is approximately between 1.0 and 9.0 DCV when using the 3E-5370 Temperature Sensor Group. Results:

• FROM 1.0 TO 7.0 (9.0) DCV – The voltage is

between approximately 1.0 and 7.0 DCV (9.0 DCV for 3E-5370 Temperature Sensor Group). The signal voltage at the sensor is correct.

B. Push the 7X-1710 Cable Probes in the back of the sensor connector along side of the +V and ground circuit wires.

Repair: The harness and the main display module are working properly. The voltage that is measured is correct. The sensor has failed. Replace the sensor.

C. Measure the system voltage.

Proceed to test step 3.

Expected Result: The voltage that is measured is between 7.5 and 8.5 DCV.

• GREATER THAN 7.0 (9.0) – The voltage is NOT

between approximately 1.0 and 7.0 DCV. (9.0 DCV for 3E-5370 Temperature Sensor Group). The signal voltage is not correct. The signal circuit of the machine harness is shorted to the +battery.


Repair: Repair the machine harness or replace the machine harness. Repeat this test step in order to verify that the problem has been corrected. If the problem has not been corrected replace the main display module. See Testing and Adjusting, “Module - Replace”. STOP.

• LESS THAN 1.0 DCV – The voltage is less than


Test Step 4. Perform the following diagnostic procedure: “Sensor Dynamic Operation”

1.0 DCV. The signal voltage is not correct. The signal circuit of the machine harness is shorted to ground.

Results:

Repair: Repair the machine harness or replace the machine harness. Repeat this test step in order to verify that the problem has been corrected. If the problem has not been corrected replace the main display module. See Testing and Adjusting, “Module - Replace”.

• REPAIRED, OK – STOP.

STOP.


Test Step 3. CHECK THE SIGNAL CIRCUIT FOR THE MACHINE HARNESS . A. At the machine harness connector for the main display module, identify the signal and ground circuits. Note: DO NOT DISCONNECT THE HARNESS CONNECTOR. B. Push the 7X-1710 Cable Probes in the back of the machine harness connector along side of the signal and ground circuit wires. C. Measure the signal voltage. D. Compare this measurement with the voltage that was measured in the previous test “Check the signal voltage”. Expected Result: The main display module is receiving a valid signal voltage of 1.0 to 7.0 DCV. Results:

• OK – The main display module is receiving a valid

signal voltage. If the problem has been corrected exit this procedure. No further testing is required. If the problem still persists, further testing is required. Proceed to test step 4.

• NOT OK – The voltage is not the same as in

the previous test “Check the signal voltage”. The machine harness has an open in the signal or ground circuits.

• OK – STOP.

i01396902

Sensor Dynamic Operation System Operation Description: Note: The main display module is connected.


Table 22

Table 23

Sensor Voltage Specifications For Sensor Dynamic Test

Sensor Voltage Specifications For Sensor Dynamic Test

(1)

100-3055 Temperature Sensor And 131-0427 Temperature Sensor Temperature

Signal Voltage(2)

(1)

3E-5370 Temperature Sensor Group And 131-0784 Temperature Sensor

Duty Cycle

Temperature

Signal Voltage(2)

Duty Cycle

−40 to 20°C (−40 to −4°F)

1.0 to 1.1 DCV

10 to 11%

−40 to 20°C (−40 to −4°F)

0.8 to 1.5 DCV

4 to 11%

−20 to 0°C (−4 to 32°F)

1.1 to 1.4 DCV

11 to 15%

−20 to 0°C (−4 to 32°F)

1.5 to 2.5 DCV

11 to 22%

0 to 20°C (32 to 68°F)

1.4 to 2.0 DCV

15 to 23%

0 to 20°C (32 to 68°F)

2.5 to 3.7 DCV

22 to 34%

20 to 40°C (68 to 104°F)

2.0 to 3.1 DCV

23 to 37%

20 to 40°C (68 to 104°F)

3.7 to 4.8 DCV

34 to 46%

40 to 60°C (104 to 140°F)

3.1 to 4.5 DCV

37 to 55%

40 to 60°C (104 to 140°F)

4.8 to 6.0 DCV

46 to 59%

60 to 80°C (140 to 176°F)

4.5 to 5.7 DCV

55 to 71%

60 to 80°C (140 to 176°F)

6.0 to 7.2 DCV

59 to 71%

80 to 100°C (176 to 212°F)

5.7 to 6.6 DCV

71 to 82%

80 to 100°C (176 to 212°F)

7.2 to 8.1 DCV

71 to 81%

100 to 120°C (212 to 248°F)

6.6 to 7.2 DCV

82 to 89%

100 to 120°C (212 to 248°F)

8.1 to 8.8 DCV

81 to 87%

120 to 140°C (248 to 275°F)

7.2 to 7.4 DCV

89 to 93%

120 to 140°C (248 to 275°F)

8.8 to 9.2 DCV

87 to 92%

(1) (2)

If desired, use these specifications with the following procedure. These voltages are guidelines for troubleshooting and are not considered exact. The tolerance is ± 10%, depending on the condition of the harness. Most important is that the output voltage changes smoothly as the temperature changes.

(1) (2)

If desired, use these specifications with the following procedure. These voltages are guidelines for troubleshooting and are not considered exact. The tolerance is ± 10%, depending on the condition of the harness. Most important is that the output voltage changes smoothly as the temperature changes.

To use the following procedure, it is necessary to know the connector contact of the main display module and the contact that corresponds to the service code. See the Electrical System Schematic in the Service Manual for the machine in order to determine the proper connector contact of the main display module. Use the 7X-1710 Cable Probe on the connector contact of the sensor signal wire on the main display module. Note: The sensors are provided power from the main display module . Therefore, the main display module must be connected in order for the sensors to function. Two items are checked in this test:

• A sensor signal is present at the main display module.

• For an increase and/or a decrease in the system that is being monitored, the signal voltage will increase and/or the signal voltage will decrease.


Test Step 1. CHECK THE INITIAL SIGNAL VOLTAGE. A. The engine coolant and the temperature sensors should be below operating temperature. B. Ensure that the engine coolant and temperature sensors are below normal. Ensure that the key switch is OFF and that the sensor is connected to the machine harness. C. Turn the key switch to the ON position. DO NOT START THE ENGINE.

B. At the machine harness connector for the main display module, measure the voltage (DCV) between the signal contact and frame ground. C. For the correct operation, the voltage (DCV) is greater (and increases smoothly without step increases) than the voltage that was recorded in the previous test “Check the initial signal voltage”. Note: The larger the change in the system that is being monitored, the greater the difference between the voltages of this test “Check the signal voltage with new conditions” and the previous test “Check the initial signal voltage”.

D. At the machine harness connector for the main display module, measure the voltage and record the voltage (DCV) between the signal contact and frame ground. For correct operation, the approximate voltage is between 1.0 and 7.0 DCV. For the 3E-5370 and 131-0784 Temperature Sensor Groups the approximate voltage is between 1.0 and 9.0 DCV.

• OK – The voltage increase during the test

Note: When precise specifications for the signal voltage are necessary, use the specifications that are listed in the provided tables.

• NOT OK – The voltage does not increase during

Expected Result: The voltage that is measured is within the specifications.

Expected Result: The voltage increases during the test procedure. Results: procedure and the sensor operates smoothly. The sensor has not failed. STOP. the test procedure. The probable cause is a failed sensor. Repair: The sensor has failed. Replace the sensor. STOP.

Results:

• YES – The approximate voltage is between 1.0

and 7.0 DCV. For the 3E-5370 and 131-0784 Temperature Sensor Groups the approximate voltage is between 1.0 and 9.0 DCV. The signal voltage to the main display module is correct. Proceed to test step 2.

• NO – The approximate voltage is NOT between

1.0 and 7.0 DCV. For the 3E-5370 and 131-0784 Temperature Sensor Groups the approximate voltage is NOT between 1.0 and 9.0 DCV. The signal voltage to the main display module is not correct. The probable cause is a failed sensor. Repair: The sensor has failed. Replace the sensor. STOP.

Test Step 2. CHECK THE SIGNAL VOLTAGE WITH THE NEW CONDITIONS. A. Increase the temperature, the pressure or the fuel level of the system that is being tested. The following procedures are examples: run the engine in order to increase the engine coolant temperature, operate the implement controls in order to increase the hydraulic oil temperature, and add fuel in order to increase the fuel level.

i01397975

Fuel Level Sender SMCS Code: 1273-038-UN System Operation Description: For the most accurate specifications for the sender, see the table “Resistor, Solenoid And Sender Specification”. This table is located in the Electrical System Schematic for the machine that is being serviced.

CHECK THE SENDER A. Disconnect the sender from the machine harness. B. Measure the resistance between the two contacts of the sender. The following data is the correct approximate resistance: 106-3535 Level Sender Assembly and 134-3033 Fuel Level Sender Empty tank ................................. 240 to 260 Ω Half tank ....................................... 97 to 118 Ω Full tank ......................................... 27 to 40 Ω


104-5546 Level Sender Assembly, 115-2086 Fuel Level Sender, 121-3174 Fuel Level Sender, 136-1617 Fuel Level Sender, 137-5156 Fuel Level Sender, 150-2995 Fuel Sender, and 151-1399 Sender Empty tank ..................................... 92 to 98 Ω Full tank .......................................... 0 to 3.5 Ω

Test Step 1. CHECK FOR AN OPEN IN THE HARNESS A. Locate the switch that corresponds to the alert indicator that is located on the main display module. (If necessary, use the Electrical System Schematic to assist in locating the switch.) B. Disconnect the signal wire from the switch.

9X-4942 Fuel Level Sender Empty tank ..................................... 80 to 85 Ω Half tank ......................................... 40 to 43 Ω Full tank ............................................. 0 to 2 Ω C. Actuate the sender by hand while you are measuring the resistance.

C. Place a jumper wire from the signal wire to the ground wire. Expected Result: The alert indicator is no longer active on the main display module.

D. The resistance should change as the sender is actuated through the empty range to the full range.

Results:

Expected Result:

• OK – The alert indicator is no longer active on the main display module.

The resistance that is measured is within the specifications. Results:

STOP.

• OK – The resistance for the fuel level sender is correct. STOP.

• NOT OK – The resistance for the fuel level sender is NOT correct.

display module. The machine harness is open or the ECM has failed. Proceed to test step 2.

A. Remove the jumper that was used in the previous test step.

STOP. i01968414

Switch Circuits SMCS Code: 1435-038; 7332-038 System Operation Description: When a filter has been replaced and the bypass switch continues to indicate that a problem exists, further troubleshooting is necessary to isolate the fault. Refer to the Systems Operations, “Switches” section for additional information on the individual switches. The possible causes of these failures are listed below:

• The signal circuit in the machine harness is open.

• The ECM has failed.

• NOT OK – The alert indicator remains on the main Test Step 2. CHECK THE VOLTAGE OF THE ECM.

Repair: Replace the fuel level sender.

• The switch has failed.

Repair: The switch has failed. Check or replace the switch.

B. The signal wire remains disconnected. C. Measure the pull-up voltage from the signal wire to the ground wire with a digital multimeter. Expected Result: The voltage is 8 ± 0.5 volts. Results:

• OK – The voltage is 8 ± 0.5 volts. Repair: The voltage is correct. The ECM has failed. It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the fault is not found, replace the ECM. See Testing and Adjusting, “Module - Replace”. STOP.

• NOT OK – The voltage is NOT 8 ± 0.5 volts. Proceed to test step 3.


Test Step 3. CHECK THE SIGNAL CIRCUIT OF THE HARNESS. A. Turn the key start switch and the disconnect switch to the OFF position. B. Use the Electrical System Schematic to trace the signal wire from the switch back to the ECM. C. Determine the signal contact (connector contact) of the machine harness at the ECM. D. Disconnect the machine harness connectors J1 and J2 from the ECM. E. At the machine harness connector for the ECM, measure the resistance between the signal contact and contact 2 of the switch. Expected Result: The resistance is less than 5 ohms. Results:


signal circuit of the harness is correct. Proceed to test step 4.

• NOT OK – The resistance is greater than 5.0 ohms.

Repair: The machine harness is not the cause of the failure. The ECM has failed. It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the fault is not found, replace the ECM. See Testing and Adjusting, “Module - Replace”. STOP.


Repair: The machine harness has failed. Repair the machine harness or replace the machine harness. STOP. i01428111

Switch Circuits SMCS Code: 1435-038; 7332-038 S/N: 1241-Up S/N: 1251-Up S/N: 1261-Up S/N: CCA1-Up S/N: CBC1-Up

Repair: The signal circuit of the harness is not correct. Repair the machine harness or replace the machine harness.

S/N: ASD1-Up

STOP.

S/N: CBK1-Up

S/N: CAF1-Up

Test Step 4. CHECK THE GROUND CIRCUIT OF THE HARNESS.

S/N: ARL1-Up

A. The key start switch and the disconnect switch remain in the OFF position.

S/N: APN1-Up

B. The machine harness connectors J1 and J2 remain disconnected. C. Use the Electrical System Schematic to trace the ground for the switch. D. At the switch, measure the resistance between the ground wire and frame ground. Expected Result: The resistance is less than 5 ohms. Results:

• OK – The resistance is less than 5 ohms.

S/N: APM1-Up

S/N: CCP1-Up S/N: AMX1-Up S/N: ALZ1-Up S/N: AMZ1-Up System Operation Description: When a filter has been replaced and the bypass switch continues to indicate that a problem exists, further troubleshooting is necessary to isolate the fault. Refer to the Systems Operations, “Switches” section for additional information on the individual switches. The possible causes of these failures are listed below:

• The signal circuit in the machine harness is open.


• The switch has failed. • The ECM has failed. Test Step 1. CHECK FOR AN OPEN IN THE HARNESS A. Locate the switch that corresponds to the alert indicator that is located on the main display module. (If necessary, use the Electrical System Schematic to assist in locating the switch.)

Repair: The voltage is correct. The ECM has failed. It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the fault is not found, replace the ECM. See Testing and Adjusting, “Module - Replace”. STOP.

• NOT OK – The voltage is NOT 8 ± 0.5 volts. Proceed to test step 3.

B. Disconnect the signal wire from the switch.

Test Step 3. CHECK THE SIGNAL CIRCUIT OF THE HARNESS.

C. Place a jumper wire from the signal wire to the ground wire.

A. Turn the key start switch and the disconnect switch to the OFF position.

Expected Result:

B. Use the Electrical System Schematic to trace the signal wire from the switch back to the ECM.

The alert indicator is no longer active on the main display module. Results:

•

OK – The alert indicator is no longer active on the main display module.

C. Determine the signal contact (connector contact) of the machine harness at the ECM. D. Disconnect the machine harness connectors J1 and J2 from the ECM.

Repair: The switch has failed. Check or replace the switch.

E. At the machine harness connector for the ECM, measure the resistance between the signal contact and contact 2 of the switch.

STOP.

Expected Result:

• NOT OK – The alert indicator remains on the main display module. The machine harness is open or the ECM has failed. Proceed to test step 2.

Test Step 2. CHECK THE VOLTAGE OF THE ECM. A. Remove the jumper that was used in the previous test step. B. The signal wire remains disconnected.

The resistance is less than 5 ohms. Results:


signal circuit of the harness is correct. Proceed to test step 4.


C. Measure the pull-up voltage from the signal wire to the ground wire with a digital multimeter.

Repair: The signal circuit of the harness is not correct. Repair the machine harness or replace the machine harness.

Expected Result:

STOP.

The voltage is 8 ± 0.5 volts. Results:

• OK – The voltage is 8 ± 0.5 volts.

Test Step 4. CHECK THE GROUND CIRCUIT OF THE HARNESS. A. The key start switch and the disconnect switch remain in the OFF position. B. The machine harness connectors J1 and J2 remain disconnected. C. Use the Electrical System Schematic to trace the ground for the switch.


D. At the switch, measure the resistance between the ground wire and frame ground.

Table 24

Alternator Specifications

Expected Result:

Peak Current Rating (Amps)

The resistance is less than 5 ohms.

Minimum Peak Current (Amps)

Results:

12 Volt Alternators

• OK – The resistance is less than 5 ohms.

8C-5535

32

28

7N-4784, OR-5201

40

36

6T-1396, 7T-2096, 8C-5908, OR-3654

51

46

9W-2648, 9W-2949, 8T-9700, 105-2811(IG), OR-4327(IG), 105-2812(IG), OR-9273(IG), 34-3268, 68-4139, 3E-7295(D+), 7T-2876(D+), 100-8223

55

49

7G-7889

60

54

8C-5510(I), OR5200

61

55

8N-2268

75

68

3E-7892, OR-3616

85

77

105-2813(IG), OR-9274(IG), 105-2814(IG), OR-4328(IG), 149-2064(REG), OR-9410(REG), 9X-0341(D+)

90

81

8C-6163, OR-1699, 107-2519

105

95

167-7816

110

99

9X-6796, 9X-9096, 121-4134, 121-4136, OR-3527

115

104

3E-8827, 121-4135, 117-1379(I)

130

117

152-8746

135

122

125-9597, OR-8332

145

131

200-2232

67.5

26

169-3345

50

30

200-8281

67.5

26

2P-1204, 3Y-8200

19

17

2Y-8310

21

19

6T-1395, 7T-2095, OR-3653

33

30

6N-9294, OR-5217, OR-3482

35

32

5N-5692, OR-2698

45

41

5S-9088, 100-5047, 112-5041, 3E-7578, OR-5206, OR-3667, OR-3668

50

45

Repair: The machine harness is not the cause of the failure. The ECM has failed. It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the fault is not found, replace the ECM. See Testing and Adjusting, “Module - Replace”. STOP.


Repair: The machine harness has failed. Repair the machine harness or replace the machine harness. STOP. i01969322

Charging System SMCS Code: 1406-038 System Operation Description: Often when problems with the charging system are being investigated, the alternator is not the problem. If a low battery condition is present test the batteries first. See Special Instruction, SEHS7633, “Battery Test Procedure” for more information. If the engine cranks slowly, then test the starting system. See Service Magazine, SEPD0020, “Testing The Starter On The Engine” for more information. If a warning indicator for the charging system is ON, see Service Magazine, SEBD1751, “Difference Between Alternator Indicator In Electronic Monitoring System (EMS) And Low Voltage Indicator In Operating Monitoring System (OMS)”. Note: Severely discharged batteries can cause low system voltage. This can occur even while the engine is running above idle, and the alternator is working properly. Proper low engine idle is also important.

24 Volt Alternators

(continued)


Results:

(Table 24, contd)

Alternator Specifications Peak Current Rating (Amps)

Minimum Peak Current (Amps)

• Method 1 – The alternator has a “1”, “REG”, or “D+” terminal. Proceed to test step 2.

• Method 2 – The alternator is self-excited. Proceed to test step 4.

109-2362, 9W-3043 , OR-3652(D+), 112-8032

55

50

3E-7772(IG), OR-9437(IG), 105-3132(IG), 4N-3986, OR-5203

60

54

155-7434, 132-2156(I), 107-7977(I), OR-8279(I)

70

63

169-4319, 167-7812

75

67.5

107-7976, 114-2401, OR-8997, 3E-7577, OR-3615

75

68

165-5140

100

90

B. Verify voltage at the excitation terminal. Connect the red lead from a multimeter to the excitation terminal. Connect the black lead to a ground source (alternator case ground).

9X-7803, OR-3749

100

90

C. Read the voltage that is shown on the multimeter.

• Method 3 – The alternator has an “IG” terminal. Proceed to test step 3.

Test Step 2. CHECK THE RESISTANCE IN THE EXCITATION CIRCUIT. A. Turn the key start switch to the ON position.

Parts-Service Only Discontinued 12 Volt Alternators

Expected Result:

6T-1193

18

16

7N-6118, 6N-5460, 4N-4540

40

36

The voltage reads at least .2 volts.

6T-1195

42

38

Results:

7X-1340

45

41

9G-6079, 6T-1194

63

57

Parts-Service Only Discontinued 24 Volt Alternators 9G-6081, 6T-1196

40

36

D+ - Diode trio output. Alternator requires external excitation. REG - Regulator Terminal. Alternator requires external excitation. I - Ignition Terminal. Alternator can be externally excited through this terminal. IG - Ignition Terminal. System voltage must be supplied to this terminal to turn on the alternator. Some of these alternators use the IG terminal as a sense terminal.

Test Step 1. DETERMINE THE ALTERNATOR EXCITATION METHOD. A. Check the rear of your alternator in order to determine the method of excitation. See table 24 in order to verify the proper alternator excitation. Expected Result: Test method 1. These alternators have a “1”, “REG”, or “D+” terminal. Test method 2. These alternators are self-excited. Test method 3. These alternators have a “IG” terminal.

• YES – The voltage reads .2 volts or more. The

excitation circuit is correct. Proceed to test step 4.

• NO – The voltage is less than .2 volts. There is a problem in the wiring harness to the alternator or there is a poor electrical connection. Correct the problem and operate the machine. Watch for a recurrence of the problem. STOP.

Test Step 3. CHECK THE RESISTANCE IN THE EXCITATION CIRCUIT (CONTINUED). Note: This step is only for alternators with external excitation when the terminal for excitation is labelled: “IG”. A. Turn the key start switch to the ON position. B. Verify voltage at the excitation terminal. Connect the red lead from a multimeter to the excitation terminal. Connect the black test lead to a ground source (alternator case ground). Note: For G3B, K3A, and L3A alternators, Insert a 7X-1710 Multimeter Probe Group into the rear of the middle wire in the connector. See figure 83 below. Insert the probes spoon lead between the seal and the wire that surrounds the wire and the outer shell of the connector. Do not insert the probe between the wire insulation and the black seal. This terminal (IG) is the terminal for excitation.


• NO – The voltage is less than system voltage. Proceed to test step 7.

Test Step 5. CHECK THE OPERATION OF THE ALTERNATOR. A. The voltmeter remains connected between the “B+” terminal and the case of the alternator. B. Start the machine. Set the throttle to at least 75 percent. Read the voltage on the voltmeter. Make a note of the voltage that was measured. Expected Result: The voltage measurement is greater than the voltage that was recorded in the previous test step “Check The System Voltage”. Results: Illustration 83

g00496660

Special wire probe technique for G3B, Y3A, and L3A alternators.

C. Read the voltage that is shown on the multimeter. Expected Result: The voltage measurement is within .5 volts of the battery voltage. Results:

• YES – The voltage reads battery voltage. The excitation circuit is correct. 4.

• NO – The voltage that is measured is more than a .5 volt less than the battery voltage. There is a problem in the wiring harness to the alternator or there is a poor electrical connection. Correct the problem and operate the machine. Watch for a recurrence of the problem. STOP.

Test Step 4. CHECK THE SYSTEM VOLTAGE. A. Before you start the machine, connect a voltmeter between the “B+” terminal and the case of the alternator. Turn OFF all electrical loads. B. Turn the key to the ON position but do not start the engine. Read the voltage on the voltmeter. Make a note of the voltage that was measured. Expected Result: This voltage should be approximately system voltage. Results:

• YES – The voltage is approximately system voltage. Proceed to test step 5.

• VOLTAGE HIGHER – The voltage measurement

is greater than the voltage that was observed in the previous test step “Check The System Voltage”. The voltage is also less than the maximum voltage that is listed in the specifications for the alternator. The alternator is partially charging the battery. Proceed to test step 6.

• VOLTGE TOO HIGH – The voltage measurement

is greater than the voltage that was observed in the previous test step “Check The System Voltage”. The voltage is also greater than the maximum voltage that is listed in the specifications for the alternator. The alternator is over charging. Proceed to test step 19.

• VOLTAGE LOWER – The voltage is not higher

than the voltage that was observed in the previous test step. Proceed to test step 7.

Test Step 6. TEST THE ALTERNATOR OUTPUT. Note: For the proper output current, refer to table 24. A. Ensure that the batteries are NOT fully charged. Note: A fully charged battery may have open circuit voltage above 12.5 volts on 12 volt systems. 24 volt systems may be as high as 25 volts. B. If the batteries are fully charged, then crank the engine for 30 seconds. This action reduces the battery voltage. Operate the lights for 10 minutes while the engine is off as an alternative. C. Connect the 9U-5795 Current Probe or 8T-0900 Ammeter to a DMM (digital multimeter). The multimeter must have a peak hold feature. Clamp the probe around the alternator output wire “B+”. Before you clamp the probe around the wire, ensure that the probe is “zeroed”.


D. Set the digital multimeter to “peak hold” or “max mode” on the “mV” scale.

Test Step 8. TEST THE CHARGING CIRCUIT.

E. Turn on all electrical accessories: lights, air conditioning, and radio.

A. Verify that the nut on the “B+” alternator terminal is tight. Also, verify that the wire has a good connection to the “B+” terminal.

F. Start the machine, and immediately set the throttle to at least 75%. The peak current will appear on the voltmeter in “peak hold” or “max” mode. Expected Result: The current reading should be at least 90% of the specified peak output. Results:

• YES – The current is at least 90% of the specified peak output. Proceed to test step 13.

• NO – The current is less than 90% of the specified peak output. Proceed to test step 7.

Test Step 7. CHECK THE DRIVE SYSTEM OF THE ALTERNATOR. A. Check the condition of the alternator drive belt. Clean the pulley and replace the drive belt if the drive belt is oily. Dry the drive belt if the belt is wet. Replace the drive belt, if the belt is worn. B. Check the tension of the alternator drive belt. Adjust the drive belt to the correct tension.

B. Many Caterpillar machines are equipped with a connector for the 6V-2150 Starting/Charging Analyzer. Use of this tester replaces the remainder of this test step. To operate the analyzer, refer to Tool Operating Manual, SEHS7768, “Using the 6V-2150”. C. Start the engine and set the throttle to at least 75 percent. Turn ON all electrical accessories for the remainder of this test step. Allow the engine to run for at least 3 minutes before continuing. D. Measure the voltage between the “B+” alternator terminal and the alternator case ground. Make a note of the measured voltage. Perform the next measurement immediately. E. Measure the voltage across the battery. Put the red lead on the battery positive terminal, and put the black lead on the battery negative terminal. Make a note of the voltage that was measured. Expected Result:

C. Check the nut on the alternator pulley. Tighten the nut if the nut is loose.

The voltage at the battery should be less than the voltage at the alternator. The difference in voltages should not be more than 1 volt on 12 volt systems. The difference should not be more than 2 volts on 24 volt systems.

Expected Result:

Results:

The drive system of the alternator is functioning correctly. No corrections to the drive system were necessary.

• YES – The voltage at the battery is less than the

Results:

• YES – The drive system of the alternator

is functioning correctly. No corrections were necessary. Proceed to test step 8.

• NO – The drive system of the alternator was not

functioning correctly. Corrections were necessary. Repair: Ensure that the problems have been corrected. Exit this procedure and retest the alternator charging system. STOP.

voltage at the alternator. Also, the difference in voltages is less than 1 volt for 12 volt systems and the difference is less than 2 volts for 24 volt systems. The wiring that is related to the alternator is correct at this time. Repair: There is an internal problem with the alternator. Repair or replace the alternator. STOP.

• NO – The voltage at the battery is less than the

voltage at the alternator. However, the difference in voltages is greater than 1 volt for 12 volt systems and the difference is greater than 2 volts for 24 volt systems. Proceed to test step 9.


Test Step 9. TEST THE POSITIVE SIDE OF THE CHARGING CIRCUIT. A. Measure the voltage between the frame ground and the “B+” alternator terminal. Make a note of the voltage that was measured. Perform the next measurement immediately. B. Measure the voltage between the frame ground and the + battery post. Make a note of the voltage that was measured. Expected Result: The voltage difference does not exceed 1 volt on 24 volt systems or 0.5 volts on 12 volt systems. Results:

• YES – The voltage difference does not exceed

the tolerance. The positive circuit is good. Proceed to test step 10.

• NO – The voltage difference exceeds the tolerance.

Repair: There is high resistance in the positive side of the charging circuit that is caused by one of the following conditions:

• An electrical connection has loosened. •

An electrical connection has corroded.

• The main relay has failed. •

A circuit breaker has failed.

Repair the problem or replace any component that has failed. Exit this procedure and retest the alternator charging system. STOP.

Test Step 10. TEST THE NEGATIVE SIDE OF THE CHARGING CIRCUIT. A. Check the voltage between the negative battery post and the alternator case ground. Expected Result: The voltage does not exceed 1 volt on 24 volt systems or 0.5 volts on 12 volt systems. Results:

• YES – The voltage difference does not exceed the tolerance. The negative circuit is good. Proceed to test step 11.

• NO – The voltage difference exceeds the tolerance.

Repair: There is high resistance in the negative side of the charging circuit that is caused by one of the following conditions:

• An electrical connection has loosened. • The alternator ground has loosened. • The engine ground has opened. Repair the problem or replace any component that has failed. Exit this procedure and retest the alternator charging system. STOP.

Test Step 11. TEST THE CIRCUIT OF THE “R” TERMINAL. A. Start the engine and set the throttle to at least 75%. B. Connect a voltmeter between the “B+” terminal and the alternator case ground. C. Disconnect the wire from the “R” terminal. Select “YES” if the “R” terminal is not used on the machine. Expected Result: The voltage does not change. Results:

• YES – The voltage does not change. Proceed to test step 12.

• NO – The voltage rises and the alternator begins charging.

Repair: The wire to the “R” terminal is shorted. Repair the wiring or replace the wiring. Exit this procedure and retest the alternator charging system. STOP.

Test Step 12. RESTORE THE RESIDUAL MAGNETISM OF THE ROTOR. A. Connect one end of a jumper wire to the “B+” terminal (D+ terminal for K1, N1, and N3) of the alternator. B. Connect the other end of the jumper wire to the “R” terminal of the alternator for two seconds. Expected Result: The voltage output rises on the “B+” terminal. The residual magnetism of the rotor has been restored.


Results:

• YES – The voltage output rises. The residual

magnetism of the rotor has been restored. The alternator is now charging. Repair: Exit this procedure and retest the alternator charging system. STOP.

• NO – The voltage output does not rise. Repair: There is an internal problem with the alternator. Repair or replace the alternator. STOP.

Test Step 13. TEST FOR UNDESIRABLE CURRENT FLOW IN THE ALTERNATOR CHARGING SYSTEM. A. Turn off all of the accessories. Turn the keyswitch to the OFF position. B. Clamp a 9U-5795 Current Probe or 8T-0900 Ammeter around the main ground cable. Clamp the tool with the positive side away from the battery. Reset the probe (zero) before you clamp the probe around the wire. Read the current on the meter. Make a note of the current that was measured. Expected Result: The current is below 2 amperes. The “YES” selection is dependent on the presence of a main disconnect switch on the machine that is being tested. Results:

• YES - WITH DISCONNECT SWITCH – The

current is below 2 amperes. For machines with a main disconnect switch, proceed to test step 14.

• YES - WITHOUT DISCONNECT SWITCH – The

current is below 2 amperes. For machines without a main disconnect switch, proceed to test step 15.

• NO – The current is above 2 amperes. There is a

current draw in the system. Proceed to test step 16.

Test Step 14. MEASURE THE CURRENT OF THE SYSTEM BY USING THE MAIN DISCONNECT SWITCH. A. Turn the disconnect switch to the ON position.

B. Connect an ammeter across the disconnect switch terminals. Connect the red lead to the terminal on the frame side. Connect the black lead to the terminal on the battery side. If a multimeter is being utilized for this test, use the 10A connections in order to avoid damage. C. Turn the disconnect switch to the OFF position and read the current. Make a note of the measured current. Note: The standard acceptable current draw is 50 milliamperes. A current draw above 50 milliamperes usually indicates a problem. However, some large machines with multiple electronic control modules have a higher acceptable limit. For more information, contact a Caterpillar dealer or contact the business unit that produces the machine. Expected Result: The current is below 0.050 amperes (50 milliamperes). Results:

• YES – The current is below 0.050 amperes. The

charging system is functioning properly at this time. The failure is possibly an intermittent draw in the system. The batteries may have failed. Ensure that NO accessories were ON during the test. Exit this procedure and retest the alternator charging system. STOP.

• NO – The current is above 0.050 amperes. There is a draw in the system. Proceed to test step 16.

Test Step 15. MEASURE THE CURRENT OF THE SYSTEM BY REMOVING THE NEGATIVE BATTERY CABLE. A. Disconnect the ground cable from the negative battery post. There may be more than one battery that is connected to ground. Disconnect all of the batteries that are connected to ground. Do not disconnect cables that are between batteries that are connected in series. B. Connect an ammeter between the disconnected battery ground cable and one of the negative battery terminals. Connect the red positive lead of the ammeter to the cable. The negative lead should be connected to the battery terminal. If a multimeter is being utilized for this test, use the 10 ampere connections in order to avoid damage.


Note: The standard acceptable current draw is 50 milliamperes. A current draw above 50 milliamperes usually indicates a problem. However, some large machines with multiple electronic control modules have a higher acceptable limit. For more information, contact a Caterpillar dealer or contact the business unit that produces the machine.

Test Step 17. TEST THE OUTPUT CURRENT OF THE ALTERNATOR BELOW 0.015 AMPERES.

The current is below .050 amperes (50 milliamperes).

A. Disconnect the wire from the “B+” terminal of the alternator. Set the multimeter on the 10 amp scale. Connect the red lead of the multimeter to the wire that was disconnected. Connect the black lead of the multimeter to the “B+” terminal of the alternator. Make a note of the current that was measured.

Results:

Expected Result:

• YES – The current is below 0.050 amperes. The

The current is less than 0.015 amperes.

Expected Result:

charging system is currently good. The problem is a possible intermittent current draw in the system. The batteries may have failed. Check that NO accessories were ON during the test. STOP.

• NO – The current is above 0.050 amperes. There is excessive current flow in the system. Proceed to test step 16.

Test Step 16. TEST THE CURRENT OF THE ALTERNATOR OUTPUT BELOW 2 AMPERES. A. Turn the keyswitch to the OFF position. B. Connect the 9U-5795 Current Probe or 8T-0900 Ammeter to a DMM (digital multimeter). Clamp the probe around the “B+” wire of the alternator. Before you clamp the probe around the wire, ensure that the probe is “zeroed”. C. Read the current on the meter. Make a note of the current that was measured. Expected Result: The current is under 2 amperes. Results:

• YES – The current is under 2 amperes. Proceed to test step17.

Results:

• YES – The current is under 0.015 amperes. The

alternator is operating correctly. There may be a current draw on the machine. Proceed to test step 18.

• NO – The current is over 0.015 amperes. Repair: There is an internal problem with the alternator. Repair or replace the alternator. STOP.

Test Step 18. IDENTIFY THE SOURCE OF EXCESSIVE CURRENT DRAW. A. Make sure that every electrical component is turned OFF. Make sure that the keyswitch is turned OFF. Make sure that the dome lights are OFF. B. Clamp a 9U-5795 Current Probe or 8T-0900 Ammeter around the main ground cable. Clamp the tool with the positive side away from the battery. Reset the probe (zero) before clamping the probe around the wire. Use the current probe if the draw is above approximately 2 amperes. Use the Ammeter if the draw is below approximately 2 amperes.

Repair: There is an internal problem with the alternator. Repair or Replace the alternator.

C. Remove the fuses or open the circuit breakers one at a time. Check the current after each fuse has been removed or each circuit breaker has been opened. After observing the current, reinstall the fuse or close the circuit breaker. Start with the main circuits first, and proceed to smaller circuits.

STOP.

D. Check if any components on the circuit are ON.

• NO – The current is over 2 amperes.

E. If everything is OFF, then disconnect electrical components on the circuit one at a time. Monitor the current after each component is disconnected.


F. All of the components in the circuit should be disconnected. If the problem still exists, then check the wiring in the circuit. There may be circuit leakage through corrosion or circuit leakage through a short. Note: The standard acceptable current draw is 50 milliamperes. A current draw above 50 milliamperes usually indicates a problem. However, some large machines with multiple electronic control modules have a higher acceptable limit. For more information, contact a Caterpillar dealer or contact the business unit that produces the machine.

D. Measure the voltage between the “B+” terminal of the alternator and the case of the alternator. Make a note of the voltage that was measured. Perform the next measurement immediately. E. Measure the voltage across the battery. Put the red lead on the positive terminal of the battery, and put the black lead on the negative terminal of the battery. Make a note of the voltage that was measured. Expected Result:

The source of the excessive current draw was determined.

The voltage at the battery should be less than the voltage at the alternator. On systems that are 12 volt, the difference in voltages should not be more than 1 volt. On systems that are 24 volt, the difference should not be more than 2 volts.

Results:

Results:

• YES – The source of the excessive current draw

• YES – The voltage at the battery is less than the

Expected Result:

was determined.

Repair: Repair the problem or replace any component that has failed. Exit this procedure and retest the alternator charging system. STOP.

• NO – The source of the excessive current draw was not determined.

Repair: Exit this procedure and retest the alternator charging system. STOP.

Test Step 19. TEST FOR AN OVERCHARGING CONDITION FROM THE ALTERNATOR. A. Verify that the nut on the “B+” alternator terminal is tight. Also, verify that the wire has a good connection to the “B+” terminal. B. Many Caterpillar machines are equipped with a connector for the 6V-2150 Starting/Charging Analyzer. Use of this tester replaces the remainder of this test step. To operate the analyzer, refer to Tool Operating Manual, SEHS7768, “Using the 6V-2150”. C. Start the engine and set the throttle to at least 75 percent. Turn ON all electrical accessories for the remainder of this test step. Allow the engine to run for at least 3 minutes before continuing.

voltage at the alternator. Also, the difference in voltages is less than 1 volt for 12 volt systems and the difference is less than 2 volts for 24 volt systems. The wiring that is related to the alternator is correct at this time. Repair: There is an internal problem with the alternator. Repair or Replace the alternator. STOP.

• NO – The voltage at the battery is less than the

voltage at the alternator. However, the difference in voltages is greater than 1 volt for 12 volt systems and the difference is greater than 2 volts for 24 volt systems. Proceed to test step 20.

Test Step 20. TEST THE POSITIVE SIDE OF THE CHARGING CIRCUIT. A. Measure the voltage between the frame of the machine and the “B+” terminal of the alternator. Make a note of the voltage that was measured. Perform the next measurement immediately. B. Measure the voltage between the frame of the machine and the positive terminal of the battery. Make a note of the voltage that was measured. Expected Result: The voltage difference does not exceed 1 volt on 24 volt systems or 0.5 volts on 12 volt systems. Results:

• VOLTAGE OK - ALT. WITHOUT IG/S TERM. – The voltage difference does not exceed the tolerance. The positive circuit is good.


Repair: There is an internal problem with the alternator. Repair or Replace the alternator. STOP.

• VOLTAGE EXCESSIVE - ALL ALT. – The voltage difference exceeds the tolerance.

Repair: There is high resistance in the positive side of the charging circuit that is caused by one of the following conditions:

• An electrical connection has loosened. • An electrical connection has corroded. • The main relay has failed. • A circuit breaker has failed. Correct the problem. Exit this procedure and retest the alternator charging system. STOP.

• VOLTAGE OK - ALT. WITH IG/S TERM. – The

voltage difference does not exceed the tolerance. The positive circuit is good. Proceed to test step 21.

Test Step 21. ALTERNATOR OVERCHARGING TEST. A. Start the engine and set the throttle to at least 75 percent. B. Measure the voltage between the sense terminal (S) and/or the “IG” terminal to the case of the alternator. Expected Result: The voltage at the “S” terminal and/or “IG” terminal is above the specification. Results:

• YES – The measured voltage exceeds the

specification. There is an internal malfunction in the alternator. See the appropriate service manual for the alternator in order to test the internal components and connections. STOP.

• NO – The measured voltage is below the

measurement that was taken in the initial tests (B+ to alternator case). The sense circuit in the generator set has high resistance. Correct the problem. Exit this procedure and retest the alternator charging system. STOP.

94 Testing and Adjusting Section

Testing and Adjusting Section

• The test for the LCD segments for rpm, gear and

direction (8) will turn on every segment of the display. The readout looks like a “0” with an “X” and a “+”. There should be twelve of these symbols next to each other on the lamp/gear module.

Testing and Adjusting

• The alert indicators (3) and the mode indicators (7) for the lamp/gear module will turn ON.

i01916579

System Self Test

• Tachometer gauge (6) and gauges (5) jump to

half scale. The gauges go to zero. The gauges then go to full scale. After reaching full scale, the tachometer and the gauges return to the current machine values.

SMCS Code: 7490-038

• The actual transmission gear readout (8) turns on every segment of the readout. The readout looks like a “0” with an “X” and a “+”. There should be two of these symbols next to each other.

• Ground speed readout (7) turns on every segment

of the readout. The readout looks like “188”. “MPH” and “km/h” are both turned ON.

• The action lamp turns ON. • The action alarm SOUNDS once. Illustration 84

g00296905

Caterpillar Monitoring System (1) Quad gauge module. (2) Speedometer/tachometer module. (3) Main display module. (4) Alert indicators. (5) Gauges. (6) Tachometer gauge. (7) Speed readout. (8) Transmission gear readout. (9) Display area.

The self test verifies that the main display module and the display modules are operating properly. The main display module performs an automatic self test when the key start switch is turned from the OFF position to the ON position. The internal circuits and the outputs (displays, action lamp and action alarm) are automatically checked. The operator must observe the outputs in order to determine if the modules and the outputs are operating properly. The alert indicators and the display area are tested for approximately one second:

• All alert indicators (4) FLASH. • Display area (9) shows: unit indicators, “SERV

CODE” indicator, symbol for service meter, and “888.X.8.8” on the six digit display area.

The display modules are tested for approximately three seconds:

The main display module then goes into the normal mode of operation. The main display module can also scroll through the modes if the inputs to the operator switch, the service switch or the clear switch are grounded. The module is operating properly if the main display module operates, as described. There is a problem with the harness code or the module has failed if the main display module does not operate, as described. In order to check the harness code, see Troubleshooting, “ Harness Code ”. i01547858

Wiring Harness (Open Circuit) - Test SMCS Code: 1408-081 An open is a failure of an electrical circuit that results in no flow of electrical current. An open circuit is usually caused by failed electrical wires or a poor connection of electrical connectors. If an electrical wire or a connection is broken, the flow of electrical current through the circuit is interrupted. A normally closed circuit will have less than 5 ohms of resistance. The following procedure explains the test for an open circuit:


Reference: For a complete electrical schematic, refer to Electrical System Schematic for the machine that is being serviced. TEST FOR AN OPEN CIRCUIT. 1. Identify the connectors and the wire numbers of the suspect circuits. Use the Electrical System Schematic of the machine to identify the circuits. 2. Turn the key start switch and the disconnect switch to the OFF position.

TEST FOR A SHORT CIRCUIT. 1. Identify the connectors and the wire numbers of the suspect circuits. Use the Electrical System Schematic of the machine to identify the circuits. 2. Turn the key start switch and the disconnect switch to the OFF position. 3. Disconnect the component and the ECM from the wiring harness.

3. Disconnect the component and the ECM from the wiring harness.

4. At the machine harness connector for the ECM, place one of the multimeter probes on the contact of the suspect wire.

4. At one of the disconnected harness connections, place a jumper wire from the contact of the suspect wire to frame ground.

5. Use the other multimeter probe to check the resistance across all other contacts in the connector(s) of the ECM and frame ground.

5. At the other connector of the machine harness, use the multimeter probes to measure the resistance from the contact of the suspect wire to frame ground. Expected Result: The resistance is less than 5 ohms. OK – The resistance is less than 5 ohms. The harness circuit is correct. Stop. NOT OK – The resistance is greater than 5000 ohms. There is an open in the machine harness. Repair: Repair the machine harness or replace the machine harness. Stop. i01547498

Wiring Harness (Short Circuit) - Test SMCS Code: 1408-081 A short circuit is a failure of an electrical circuit that results in undesired electrical current. Usually, a short circuit is a bypass of the circuit across a load. For example, a short across the wires in a circuit for a lamp produces too much current in the wires but no current is felt at the lamp. The lamp is shorted out. The resistance in a normal circuit is greater than 5000 ohms. The following procedure explains the test for a short circuit: Reference: For a complete electrical schematic, refer to Electrical System Schematic for the machine that is being serviced.

Expected Result: The resistance is greater than 5000 ohms for all the measurements. OK – The resistance is greater than 5000 ohms for all the measurements. The harness circuits are correct. Stop. NOT OK – The resistance is less than 5 ohms. There is a short in the machine harness. The short is between the suspected wire and the wire with the lowest resistance measurement. Repair: Repair the machine harness or replace the machine harness. Stop.


i01744672

Wiring Harness (Short Circuit) - Test SMCS Code: 1408-081 S/N: ASD1-Up S/N: ARL1-Up

NOT OK – The resistance is less than 5 ohms. There is a short in the machine harness. The short is between the suspected wire and the wire with the lowest resistance measurement. Repair: Repair the machine harness or replace the machine harness. Stop.

S/N: APM1-Up S/N: APN1-Up S/N: ATS1-Up A short circuit is a failure of an electrical circuit that results in undesired electrical current. Usually, a short circuit is a bypass of the circuit across a load. For example, a short across the wires in a circuit for a lamp produces too much current in the wires but no current is felt at the lamp. The lamp is shorted out. The resistance in a normal circuit can vary, but the resistance between a particular circuit and other unrelated circuits is always greater than 5000 ohms. The following procedure explains the test for a short circuit: Reference: For a complete electrical schematic, refer to Electrical System Schematic for the machine that is being serviced. TEST FOR A SHORT CIRCUIT. 1. Identify the connectors and the wire numbers of the suspect circuits. Use the Electrical System Schematic of the machine to identify the circuits.

i01205456

Electrical Connector - Inspect SMCS Code: 7553-040-WW Intermittent electrical problems are often caused by poor connections. Use the following checks as a reference for inspecting connectors. 1. Check the connection of the connectors.

• Ensure that the locking rings are properly locked.

• Ensure that locking clips are used on Sure Seal connectors.

• Ensure that the center of the connector is tight. • Ensure that the connector pins and sockets align properly.

2. Check the wires at the connector.

• Ensure that the wires enter the back of the connector straight.

2. Turn the key start switch and the disconnect switch to the OFF position.

• Ensure that each wire is properly crimped into

3. Disconnect the component and the ECM from the wiring harness.

• Ensure that each connector contact is properly

4. At the machine harness connector for the ECM, place one of the multimeter probes on the contact of the suspect wire. 5. Use the other multimeter probe to check the resistance across all other contacts in the connector(s) of the ECM and frame ground.

the proper connector contact.

locked into the connector contact. When the connector contact is locked properly, the contact (wire) cannot be pulled out of the connector body without excessive force.

3. Check each wire for nicks or signs of abrasion in the insulation. 4. Check for moisture at the connector.

Expected Result: The resistance is greater than 5000 ohms for all the measurements.

• Check for damaged connector seals or lost

OK – The resistance is greater than 5000 ohms for all the measurements. The harness circuits are correct.

• Check for missing or loose wire hole plugs.

Stop.

connector seals.

• Check for wires that do not enter the connector properly.


• If the wires enter the connector at an angle,

Expected Result: The module has been successfully replaced and the module has completed the self test.

• Moisture can enter the connector through the

Results:

there may not be a good seal between the connector and the wire insulation. wire insulation.

5. Check for dirty contacts or corroded contacts.

• Clean contacts with a cotton swab or a soft brush and denatured alcohol only.

6. Check each pin and each socket.

• Check each contact of the connector for a snug fit by using a new pin and socket. The new contact should stay connected if the connector is held with the contacts that are facing down.

i01855646

Module - Replace SMCS Code: 7490-510 Prior to replacement of a module, ensure that replacement is absolutely necessary. A diagnostic code is seldom caused by the module. Always ensure that the machine code is correct for the machine. Also ensure that the power is available to the main display module. The system voltage is required between the contacts 1 and 2 of the connector for the main display module. To check the machine code, see System Operation, “Harness Code Mode”.

Procedure 1. Replace the module. a. Turn the key start switch to the OFF position. b. Disconnect the machine harness from the module. c. Ensure that the module that is replacing the old module has the correct part number. d. Install the new module. Note: If the main display module that is replacing the old module was previously removed from service, see Testing and Adjusting, “Main Display Module Initialization - Adjust”. e. Connect the machine harness to the module. On so equipped machines, make sure that the harness code plug is installed. f. Turn the disconnect switch and the key start switches to the ON position. Make sure that the module successfully completes the self test: see Testing and Adjusting, “System Self Test”.

• YES - The module has been successfully

replaced and has completed the self test. Proceed to 2.

• NO - The module has been successfully

replaced but has not performed the self test properly. Ensure that the module is correct. Ensure that the installation is correct and ensure that no related diagnostic codes are present. STOP.

2. Setup a. Set up the optional display modules, see Systems Operation, “Setup Mode”. b. Set the desired units (English or Metric), see System Operation, “Units Mode”. Note: Once the module has been replaced successfully, see Testing and Adjusting, “Main Display Module-Flash Program”. i01104167

Main Display Module Initialization - Adjust SMCS Code: 7490-025 The initialization is an internal process within the main display module. During the initialization, the main display module listens to the CAT data link and the harness code inputs. From this information, the module learns about the machine. For example, the module learns that the information for the engine oil pressure is coming from an engine ECM. Normally, the initialization occurs when the main display module is replaced. Also, the initialization occurs when there is a change in the harness code. However, when a previously used main display module is used as a replacement, initialization could be necessary. Faults that can not be explained with the CAT data link can occur if the main display module is not initialized correctly. The service person must activate the initialization when the main display module has been previously used. Initialization is used if the module was taken out of an application that had the same machine code as the main display module that is to be removed.


Procedure For Initialization This procedure causes the initialization to occur on any main display module. Initialization requires that the main display module be powered up with a valid harness code that is different than the harness code when it was last powered down. For a list of valid harness codes, see the table for Machine Codes in System Operation, “Harness Code Mode”. 1. Code input configuration. a. Turn the key start switch to the OFF position.

d. Depending on the previous procedure that was performed, either reinstall the harness code plug (from “Code input configuration”) or reinstall the ground connector contact (from “Hard wired procedure”). e. Make sure the main display module successfully completes the self test, see Testing and Adjusting, “System Self Test”. f. Check the machine code. See System Operation, “Harness Code Mode”. Expected Result: The display module has successfully completed the self test.

b. Determine whether the harness code inputs are hard wired in the machine harness or accessible at a harness code plug. Use the Electrical System Schematic in the Service Manual for the machine.

• OK - The display module successfully

Expected Result: There is a harness code plug.

• NOT OK - The display module did not

Results:

• YES - There is a harness code plug. Remove

Results: completed the self test. STOP.

complete the self test. Exit this procedure. Determine the cause of the failure and repeat “Initialization”. STOP.

the harness code plug. Proceed to 3.

• NO - The harness code inputs are hard wired in the machine harness. Proceed to 2.

2. Hard wired procedure. a. Disconnect the machine harness from the main display module. b. At the machine harness connector for the main display module, remove the wire for one of the following contacts (3, 6, 12, 16, 22 or 31). Choose one that is connected to ground. c. With tape, secure the removed connector contact out of the way. d. Reconnect the machine harness to the main display. Results:

• CONTINUE - Proceed to 3. 3. Reconnection and verification. a. Turn the disconnect switch and the key start switches to the ON position. b. Various indicators in the Caterpillar Monitoring System display area will illuminate. Wait 10 seconds. c. Turn the key switch to the OFF position.

i01519504

Main Display Module - Flash Program SMCS Code: 7490-591 Perform the following procedure in order to flash program the ECM. The ECM is flashed in order to upgrade the software. Flash programming of the ECM must also be done if the ECM has been replaced. The Caterpillar Electronic Technician (ET) contains the program WinFlash. WinFlash is used in order to load software into the ECM. The following procedure is used in order to FLASH software into the ECM for the Caterpillar Monitoring System. 1. Procedure a. Connect the 7X-1425 Data Link Cable between the 7x-1700 Communication Adapter and the Electronic Technician. b. Connect the 139-4166 Data Link Cable between the 7x-1700 Communication Adapter and the diagnostic connector of the machine. c. Turn the key to the ON position. d. Use WinFlash in order to load the software. Note: Flash programming is not allowed if the engine is running, or the machine is moving.


i01425096

Glossary of Terms SMCS Code: 7490 Abnormal – This means a condition that is not normal. The presence of an abnormal condition or an abnormal signal indicates the existence of a problem. A warning is activated in order to alert the operator. Alert Indicator – An alert indicator is a red indicator lamp that is located on the top portion of the main display module. The alert indicator notifies the operator of an abnormal condition. +Battery – This pertains to any of the harness wiring which is part of the circuit that connects to the positive battery post. +Battery voltage is also referred to as system voltage. Caterpillar Electronic Technician (ET) – This is a Windows based program, that is used to service Caterpillar products. The software operates on a service tool (personal computer). Component Identifier (CID) – The CID is a diagnostic code that informs the operator of component or the system that has failed. The CID is a four digit code, that is located in the digital display area when the main display module is in service mode.

Failure Mode Identifier (FMI) – An FMI is a diagnostic code that identifies the type of failure that has occurred. The FMI consists of two digit code which is preceded by a decimal point “.”. This code is shown on the display area when the main display module is in service mode. Diagnostic Code – A diagnostic code is a failure of a component in an electronic system. An associated CID FMI identifies the type of problem. Diagnostic Event – This is a type of maintenance event. This event is displayed when an electronic control detects an abnormal condition in the electrical system. Sometimes abnormal conditions in the mechanical system can be detected through the electrical system. Gauge – This is a display device that is typically circular in shape with an indicator needle. The gauge can be a mechanical device or the gauge can be a solid state device. Ground (B-) – This is the reference point for the electrical system. On CAT products, ground is the machine frame or the engine. This is the connection point for the negative side of the battery. Floating – This describes the end of a circuit that is open. The circuit is not connected to any other component.

Clear – This is the removal of diagnostic information that is stored in the memory of the ECM. Before a failure is cleared, the failure must be on hold and the failure must not be present.

Hard Wired – Hard wired refers to an electrical connection that is made within the harness. The connections are permanent. These soldered connections or crimped connections are not meant to be altered.

Connector Contact – A connector contact is the component of a harness connector that actually makes the electrical connection. Connector contacts are either pins or sockets.

Harness – This is an assembly or a bundle of two or more wires that electrically connects system components. Typically, the harness is held together by a loom.

Detected Diagnostic Code – A detected diagnostic code is a problem that has been found by the main display module. A service code that has been recorded for the problem and the diagnostic information is available when the main display module is in service mode.

Harness Code – This refers to the grounded condition or the open circuit condition of the inputs for the harness code . The harness code provides the characteristics of the machine such as engine oil pressure, maximum engine speed, etc. The monitoring system uses this hard wired code in order to determine the module identifier (MID) that is used for data link communications.

Diagnostic – This is a process that takes place within an electronic control. The control senses the abnormal machine information. The control displays the abnormal machine information. The control stores the abnormal machine information. This stored information can aid the service technician. Display – Display refers to the gauges, indicators, or readouts within the Caterpillar Monitoring System display area.

Hertz (Hz) – This is a measure of frequency. The units are cycles per second. Hysteresis – This is a measure of the “lag time that occurs between the turn ON and turn OFF values of a switch or a sensor”. As an example, the warning lamp may turn on at 40 psi with decreasing pressure and the warning lamp may turn off at 45 psi with increasing pressure. The hysteresis is 5 psi.


Indicator – An indicator is any of the items within the Caterpillar Monitoring System display area which operate in an ON, FLASHING or OFF manner in order to bring attention to a machine condition. Jumper – A jumper is a piece of wire that is used to make an electrical connection during troubleshooting. Key Start Switch – This is an automotive type key start that provides engine cranking/starting . Lamp – This is a component of the machine electrical system that emits light by converting electrical energy into light. Light Emitting Diode (LED) – This is a solid state device. The device emits light that is visible to the human eye when an electrical current is passed through the device. The LED is used as a lamp in electronic controls because the device is very reliable. Liquid Crystal Display (LCD) – This is a type of solid state display that uses a liquid crystalline material. The material is sealed between two glass sheets. An electrical signal causes segments of the crystal material to be visible to the eye. Machine Service Connector – This is a harness connector for the machine or for engine electrical systems. The harness connector will allow the connection of a service tool for diagnostics. Module Identifier (MID) – An MID is a diagnostic code that identifies the electronic control module which diagnosed the diagnostic code. The two-digit code is displayed in the display area when the machine is in the service mode. Open Circuit – This is a condition that exists when an electrical circuit is broken. Pressure Sensor – This is a device that generates a signal that is proportional to the pressure that is sensed. Problem – This refers to the presence of an abnormal machine condition. When a problem exists, warning operation is activated and the main display module notifies the operator. Pounds per square inch (psi) – This is an English unit of pressure measurement. The measurement represents the force that is applied to one square inch. The value is measured in pounds. 6.89 kPa (1 psi) Pull up Voltage – This is the voltage that is measured on the input of an electronic control. The measurement is taken when an input device (sensor or switch) has been disconnected.

Pulse Width Modulation (PWM) – The PWM is a signal that consists of variable pulse widths at fixed intervals. The duty cycle can be varied. The frequency of a PWM signal is constant. The Caterpillar Monitoring System has sensors which provide a PWM signal to the main display module. Scroll – When you scroll through information in the display area, all available sets of diagnostic information are shown by one set at a time. A set of diagnostic information is shown briefly. Then, the display automatically advances to the next set. After all sets have been shown, the sets are repeated. Sender – This is a device that changes resistance according to a physical condition. The sender then sends a signal to a gauge. A single connection provides the signal and the power. Sensor – This is a device that monitors the physical condition of a machine system. The sensors can monitor the conditions that are listed here: pressure, temperature, flow, and mechanical movement. The sensors convert the condition into an electrical signal that can be understood by an electronic control. Service Code – This is a type of maintenance code that describes a condition that has been identified by an electronic control system. The code indicates when service is required. This code is stored in the control for the service technician. This term was previously referred to as a fault code. This code is now referred to as a service type of maintenance event. Service Tool – This is a tool that is used in order to service Caterpillar machines. This term most often refers to the service equipment that is listed here: Electronic Control Analyzer Programmer (ECAP), Caterpillar Electronic Technician (ET), a digital multimeter, and laptop computer This may also refer to any other dedicated service equipment. Short Circuit – A connection between two points in a circuit that is normally unwanted. Show – This pertains to information that is within the Caterpillar Monitoring System display area that is viewed by the operator or a service person. Signal – This is the changing voltage that is used to carry information. A signal is typically sent from a sensor to an electronic control. For example, a signal is sent from the transmission output speed sensor (TOS) to the transmission control. Signal Wire – This is the harness wire that carries the signal voltage to the electronic control. The signal is sent by any of the components that are listed here: a sensor, a switch, and any other similar components.


Speedometer/Tachometer Module – This is a display module that contains the components that are listed here: a speedometer for machine ground speed, a tachometer for engine speed, and a display for actual gear. Switch Input – This is an input to an ECM. This input may be ground. The input may be open. The input may be positive voltage (+battery). System Voltage – System voltage is the actual voltage that exists between the positive battery post and the frame ground. The system voltage is referred to as the + battery. Temperature Sensor – This is a device that generates a signal that is proportional to the change in temperature. Uncommitted Switch Input – Uncommitted switch inputs are switch inputs that function according to the application. Information from the uncommitted switch inputs is typically used to operate the alert indicators. Undetected Problem – This is a problem that is not detected by the main display module, but the problem is found by the operator or by a service technician. The many diagnostic functions of the main display module assist with the troubleshooting of undetected problems. +V – This pertains to a constant voltage that is supplied to a component. +V is provided by an electronic control module or the battery. i01857510

Connector Contact Description of Main Display Module SMCS Code: 7490-546-CY Table 25

Contact Description Of Main Module Connector 12H, 120H, 135H, 140H, 143H, 160H And 163H No.

Function

Type

Description

1

+ Battery

Input - Voltage (Power)

28 VDC

2

Ground

Ground

0 VDC

3

Harness Code 1

Switch Input - Programming

Programming Switch(1)

4

Action Alarm

Output

Alarm Driver

5

CAT Data Link +

Input/Output - Data Link

Driver/Receiver (+)

6

Harness Code 5



7

PWM/Switch 1

Sensor Or Switch Input

Unassigned

8

PWM/Switch/Sender 5

Sensor, Switch Or Sender Input

Unassigned

9

Switch /Sender 10

Switch Or Sender Input

Fuel Level (continued)


(Table 25, contd)

Contact Description Of Main Module Connector 12H, 120H, 135H, 140H, 143H, 160H And 163H No.

(1)

Function

Type

Description

10

PWM/Switch/Sender 6

Sensor, Switch Or Input

Unassigned

11

Switch 7

Switch Input

Unassigned

12

Harness Code 2



13

Action Lamp

Output

Lamp Driver

14

CAT Data Link -


Driver/Receiver (-)

15

Display Module Load

Output

Driver for Gauge Module

16

Harness Code 4



17

PWM/Switch 2


Unassigned

18

Switch/Sender 9


Articulation Angle Sender

19

Switch 1

Switch Input

Brake System Pressure Switch

20

Switch 4

Switch Input

Operator Mode Switch

21

Switch 8

Switch Input

Unassigned

22

Harness Code 3



23

Service

Switch Input

Scroll Switch

24

Sensor Power Supply

Output

Unassigned

25

Display Module Clock

Output

Driver for Gauge Sequencing

26

Frequency 1

Sensor Input - Frequency

Unassigned

27

PWM/Switch 4

Sensor or Switch Input

Unassigned

28

PWM/Switch/Sender 7


Unassigned

29

Switch 2

Switch Input

Park Brake

30

Alternator R terminal


Alternator Frequency

31

Harness Code 0



32

Switch 6

Switch Input

Hydraulic Temperature

33

Clear

Switch Input

Clear Switch

34

Display Module Power Supply

Output

9 VDC

35

Display Module Data

Input/Output

Data for Gauge Module

36

Frequency 2


Unassigned

37

PWM/Switch 3


Unassigned

38

PWM/Switch/Sender 8


Unassigned

39

Switch 3

Switch Input

Unassigned

40

Switch 5

Switch Input

Primary Steering Pressure

This pin is only used on early model machines for the 140H, 143H, 160H, And 163H. Newer machines use flash software to program the harness code.


Table 26

Contact Description Of Main Module Connector 14H, And 16H No.

Function

Type

Description

1

+ Battery

Input - Voltage (Power)

28 VDC

2

Ground

Ground

0 VDC

3

Harness Code 1


Unassigned

4

Action Alarm

Output

Alarm Driver

5

CAT Data Link +


Driver/Receiver (+)

6

Harness Code 5


Unassigned

7

PWM/Switch 1


Unassigned

8

PWM/Switch/Sender 5


Unassigned

9

Switch /Sender 10


Fuel Level

10

PWM/Switch/Sender 6

Sensor, Switch Or Input

Unassigned

11

Switch 7

Switch Input

Neutral Start Switch

12

Harness Code 2


Unassigned

13

Action Lamp

Output

Lamp Driver

14

CAT Data Link -


Driver/Receiver (-)

15

Display Module Load

Output

Driver for Gauge Module

16

Harness Code 4


Unassigned

17

PWM/Switch 2


Reverse/Backup Alarm Switch

18

Switch/Sender 9


Articulation Angle Sender

19

Switch 1

Switch Input

Brake System Pressure Switch

20

Switch 4

Switch Input

Operator Mode Switch

21

Switch 8

Switch Input

Unassigned

22

Harness Code 3


Unassigned

23

Service

Switch Input

Scroll Switch

24

Sensor Power Supply

Output

Unassigned

25

Display Module Clock

Output

Driver for Gauge Sequencing

26

Frequency 1


Ground Speed Sensor

27

PWM/Switch 4

Sensor or Switch Input

Unassigned

28

PWM/Switch/Sender 7


Unassigned

29

Switch 2

Switch Input

Park Brake

30

Alternator R terminal


Alternator Frequency

31

Harness Code 0


Unassigned

32

Switch 6

Switch Input

Hydraulic Temperature

33

Clear

Switch Input

Clear Switch

34

Display Module Power Supply

Output

9 VDC

35

Display Module Data

Input/Output

Data for Gauge Module

36

Frequency 2


Unassigned

37

PWM/Switch 3


Unassigned (continued)


(Table 26, contd)

Contact Description Of Main Module Connector 14H, And 16H No.

Function

Type

Description

38

PWM/Switch/Sender 8


Unassigned

39

Switch 3

Switch Input

Unassigned

40

Switch 5

Switch Input

Primary Steering Pressure

i01857839

System Schematic SMCS Code: 7566 These schematics are typical Caterpillar Monitoring System schematics, that show possible inputs and outputs. On some machines, certain sensors are not part of the system. However, the main display module receives the sensor information over the CAT data link from other electronic controls. For an accurate schematic of a particular machine, always see the Electrical System Schematic in the machine Service Manual.


140H, 143H, 160H And 163H

Illustration 85

g00947079


14H

Illustration 86

g00865621


16H

Illustration 87

g00947028


12H, 120H, 135H, 140H, 143, 160H, And 163H

Illustration 88

g00947030

109 Index Section

Index A Action Alarm .......................................................... Action Lamp........................................................... Additional Operator Modes.................................... Trip Fuel Consumption Mode............................. Trip Hourmeter Mode ......................................... Trip Odometer Mode .......................................... Alert Indicator Description ..................................... Alert Indicator Is Always Flashing.......................... Alert Indicator Never Flashes ................................ Articulation Gauge Calibration Mode.....................

I 36 36 13 14 13 14 25 71 72 22

C Calibration Mode ................................................... 18 Submodes.......................................................... 19 Charging System ................................................... 85 Component Description ......................................... 27 Connector Contact Description of Main Display Module ............................................................... 101 D Diagnostic Capabilities .......................................... The Caterpillar Electronic Technician (ET)......... Diagnostic Code List.............................................. Diagnostic Code Procedures................................. Diagnostic System Procedures ............................. Display Components .............................................

42 42 44 44 71 31

E Electrical Component and Connector Locations ... 40 Connector Contact Numbers for the Main Display Module ............................................................. 41 General Information ........................................... 40 Service Connector ............................................. 41 Electrical Connector - Inspect................................ 96 F Fuel Level Sender ................................................. 81 G General Information........................................... 4, 38 Introduction .......................................................... 4 Glossary of Terms.................................................. 99 H Harness Code........................................................ 73 Harness Code Mode.............................................. 12

Important Safety Information ................................... 2 Introduction............................................................ 38 M Main Display Module ............................................. 27 Inputs ................................................................. 28 Inputs/Outputs.................................................... 27 Outputs .............................................................. 30 Main Display Module - Flash Program .................. 98 Main Display Module Initialization - Adjust ............ 97 Procedure For Initialization ................................ 98 MID 030 - CID 0084 - FMI 08 ................................ 48 MID 030 - CID 0096 - FMI 03 ................................ 50 MID 030 - CID 0096 - FMI 04 ................................ 51 MID 030 - CID 0096 - FMI 08 ................................ 52 MID 030 - CID 0248 - FMI 02 ................................ 52 MID 030 - CID 0263 - FMI 03 ................................ 54 MID 030 - CID 0263 - FMI 04 ................................ 55 MID 030 - CID 0271 - FMI 03 ................................ 56 MID 030 - CID 0271 - FMI 05 ................................ 57 MID 030 - CID 0271 - FMI 06 ................................ 58 MID 030 - CID 0324 - FMI 03 ................................ 59 MID 030 - CID 0324 - FMI 05 ................................ 60 MID 030 - CID 0324 - FMI 06 ................................ 61 MID 030 - CID 0601 - FMI 08 ................................ 62 MID 030 - CID 0615 - FMI 03 ................................ 62 MID 030 - CID 0615 - FMI 04 ................................ 64 MID 030 - CID 0819 - FMI 02 ................................ 65 MID 030 - CID 0821 - FMI 03 ................................ 68 MID 030 - CID 0821 - FMI 04 ................................ 69 Modes of Operation ................................................. 8 Module - Replace .................................................. 97 Procedure .......................................................... 97 N Normal Mode ........................................................... 9 Numeric Readout Mode......................................... 12 O Odometer Mode...................................................... 11 P Pulse Width Modulated Sensor ............................. 76 Q Quad Gauge Module ............................................. 31

110 Index Section

R

W

Related Components............................................. 37 Alternator ........................................................... 37 Other Electronic Controls................................... 37

Warning Operation ................................................ 24 Wiring Harness (Open Circuit) - Test..................... 94 Wiring Harness (Short Circuit) - Test ............... 95–96

S Scrolling Mode........................................................ 11 Senders ................................................................. 33 Level Sender (Fuel) ........................................... 33 Position Sender (Articulation Angle) .................. 34 Temperature Sender .......................................... 34 Sensor Dynamic Operation ................................... 79 Sensor Signal Voltage ........................................... 77 Sensors ................................................................. 34 Frequency Sensors............................................ 34 General Information ........................................... 34 Pulse Width Modulated (PWM) Sensors............ 35 Service Meter Mode .............................................. 10 Service Mode......................................................... 14 Service Tools ......................................................... 38 4C-8195 Control Service Tool........................... 40 Changing Modes................................................ 40 Service Switches................................................ 39 Setup Mode ........................................................... 18 Speedometer/Tachometer Module ........................ 32 Switch Circuits ................................................. 82–83 Switches ................................................................ 32 Pressure Switch ................................................. 33 Rocker Switch (Operator Mode Selector) .......... 33 Temperature Switch (Hydraulic Oil) ................... 33 System Schematic............................................... 104 12H, 120H, 135H, 140H, 143, 160H, And 163H............................................................... 108 140H, 143H, 160H And 163H ......................... 105 14H .................................................................. 106 16H .................................................................. 107 System Self Test.................................................... 94 Systems Operation Section ..................................... 4 T Table of Contents..................................................... 3 Tachometer Mode................................................... 11 Tattletale Mode ...................................................... 16 Testing and Adjusting ............................................ 94 Testing and Adjusting Section ............................... 94 Troubleshooting Section ........................................ 38 U Units Mode ............................................................ 18 Using Caterpillar Electronic Technician to Determine Diagnostic Codes................................................. 46 Using Caterpillar Monitoring System to Determine Diagnostic Codes................................................. 45 Procedure .......................................................... 45

111 Index Section

©2003 Caterpillar All Rights Reserved

Printed in U.S.A.

CAT 16H service manual

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