525B Wheel Skidder and 535B Wheel Skidder Power Train Caterpillar

Use the Caterpillar Monitoring System or the Caterpillar Electronic Technician (ET) in order to determine the diagnostic codes for the power train electronic control module (ECM). After determining the diagnostic codes, refer to the corresponding test procedure for more information. Perform the procedure that corresponds to the Component Identifier (CID) and the Failure Mode Identifier (FMI) of the diagnostic code. The following table is a list of possible diagnostic codes for the power train ECM.

Table 1

Diagnostic Codes For the Power Train Electronic Control Module (ECM) Module Identifier (MID) No. 081 (1)
Perform the procedure that corresponds to the CID and the FMI of the diagnostic code during troubleshooting.
CID / FMI	Description
CID 0168- Electrical System Voltage:
FMI 01	Data valid but below normal operational range.
CID 0417 - Grapple Solenoid Relay:
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
FMI 07	Mechanical system not responding properly.
CID 0449 - Grapple Rotate Switch, CID 0450 - Tong Position Switch:
FMI 02	Data erratic, intermittent, or incorrect.
CID 0451 - Grapple Clockwise Solenoid, CID 0452 - Grapple Counterclockwise Solenoid:
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
CID 0453 - Tong Open Solenoid, CID 0454 - Tong Close Solenoid:
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
CID 00455 - Pressure Sensor (Tong Close):
FMI 00	Pressure above normal range.
FMI 01	Pressure below normal range.
CID 0621: Switch (Downshift), CID 0622: Switch (Upshift), CID 0623: Switch (Direction):
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
CID 0627 - Switch (Parking Brake):
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
CID 0637 Backup Alarm:
FMI 06	Current above normal or grounded circuit.
CID 0641 - Transmission Solenoid 1 (high forward), CID 0642 - Transmission Solenoid 2 (reverse), CID 0643 - Transmission Solenoid 3 (low forward), CID 0644 - Transmission Solenoid 4 (speed), CID 0645 - Transmission Solenoid 5 (speed), CID 0646 - Transmission Solenoid 6 (speed):
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
CID 0701 Speed Sensor (Transmission Output):
FMI 02	Data erratic, intermittent, or incorrect.
CID 0709 Solenoid (Lockup Clutch):
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.
FMI 13	Needs calibrated
CID 0740 - Solenoid (Differential Lock):
FMI 03	Voltage above normal or shorted high.
FMI 05	Current below normal or open circuit.
FMI 06	Current above normal or grounded circuit.

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For the power train Electronic Control Module (ECM), the MID is 081. This table pertains only to faults with an MID of 081.

Note: Table 1 refers to the diagnostic codes for the power train electronic control module (ECM) only. When the Caterpillar Monitoring System is in service mode, the diagnostic codes for the power train ECM are shown on the display area of the Caterpillar Monitoring System. The information for the diagnostic codes for the power train ECM is transferred via the CAT Data Link to the Caterpillar Monitoring System. This diagnostic information is shown when the Caterpillar Monitoring System is in the service mode. The Module Identifier (MID) tells the service person the ECM that is sending the diagnostic code. The MID for the power train ECM is 081. The information in Table 1 refers to only diagnostic codes with an MID of 081. The MID of other electronic control modules or components on a particular machine are listed on the electrical system schematic. Troubleshooting information for the diagnostic codes with an MID that is not 081 can be found in the service manual for that system.

Illustration 1	g00538724
Power Train Electronic Control (1) Connector J1. (2) Connector J2.

Table 2

40-Pin Connector J1
Connector Pin (1)	Function
1	+ 24 Volt ECM (Electronic Control Module) Supply (Key ON)
2	Ground
3	CAT Data Link -
4	Number 2 Clutch Solenoid (Reverse)
5	Ground
6	+ 24 Volt ECM (Electronic Control Module) Supply (Key ON)
7	Solenoid Return
8	Start Relay Coil
9	CAT Data Link +
10	Number 1 Clutch Solenoid (High Forward)
11	Number 4 Clutch Solenoid (First Speed)
12	Tong Close Solenoid
13	Transmission Neutral Switch
14	Transmission Reverse Switch
15	Switch and Sensor Ground
16	Switch and Sensor Ground
17	Number 3 Clutch Solenoid (Low Forward)
18	Grapple Rotate Solenoid (Clockwise)
19	Transmission Upshift Switch (N.C.)
20	Tong Switch OFF Position
21	Tong Close Input
22	Tong Open Input
23	Transmission Upshift Switch (N.O.)
24	Ground for Cable Skidder only
25	Transmission Downshift Switch (N.C.)
26	Transmission Downshift Switch (N.O.)
27	Parking Brake ON position
28	Differential Lock Switch to Battery (+24 Volts)
30	Transmission Forward Switch
32	Torque Converter Lockup Clutch Enable Switch
33	Grapple Rotate Switch Input (Counterclockwise)
36	Parking Brake OFF position
37	Grapple Rotate Switch Input (Clockwise)
38	Grapple Rotate Switch Input (Off)
40	Key Switch START position

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Pins that are not shown are unused.

Table 3

40-Pin Connector J2
Connector Pin (1)	Function
1	Number 6 Clutch Solenoid (Third Speed)
2	Grapple Rotate Solenoid (Counterclockwise)
3	Solenoid Return
5	Grapple Auto/Man Switch (N.C.)
7	Number 5 Clutch Solenoid (Second Speed)
8	Torque Converter Lockup Clutch Solenoid
11	Grapple Auto/Man Switch (N.O.)
13	Grapple Solenoid Return Relay Solenoid
19	Tong Open Solenoid
22	Air Inlet Heater (AIH) Signal
23	Engine Speed Return
24	Transmission Speed Return
28	Backup Alarm
29	Engine Speed Signal
34	Torque Converter Lockup Clutch Indicator
35	Transmission Speed Signal
37	Differential Lock Solenoid
38	Tong Pressure Sensor

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Pins that are not shown are unused.

Reference: For additional information about the Module Identifiers (MID) for the 525B and the 535B Wheel Skidders, refer to Schematic, "525B Wheel Skidder and 535B Wheel Skidder Electrical System" for the machine that is being serviced.

Reference: For additional information about the Caterpillar Monitoring System, refer to Systems Operation/Testing and Adjusting, SENR1394, "General Information".