COVER 5K4012 - Caterpillar

Illustration 1 g03155296
Schematic of the +8 V Sensor Supply from the Machine ECMThis diagnostic code is associated with the Machine ECM 8 V sensor power supply. The 8 V sensor power supply provides power for the Track Speed Sensors.The CID 0041 FMI 04 diagnostic code is activated when the Machine ECM detects that the voltage of the 8 V power supply circuit is lower than normal.Note: The Machine ECM is located inside the Center Console.The following conditions could cause this diagnostic code:
A sensor has failed.
The power supply circuit is shorted to a ground source.
The ECM has failed. This is unlikely.Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure, and in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: The following test procedure may create other diagnostic codes. Clear the diagnostic codes when the problem has been corrected. Verify that the CID 0041 FMI 04 is active before performing this procedure.System Response:Sensors connected to supply will not log faults.Test Step 1. CHECK THE POWER SUPPLY AT THE MACHINE ECM
Turn the disconnect switch and the key start switch to the OFF position.
At Machine ECM connector J1, use a 151-6320 Removal Tool or a similar tool to remove the supply wire and socket at contact J1-11 (wire K983-BU) and the return wire and socket at contact J1-12 (wire A275-BK) from the connector. The machine harness connector J1 remains connected to the ECM.
Turn the disconnect switch and the key start switch to the ON position.
Use the multimeter probes in order to make contact on the Machine ECM connector pins. Measure the voltage at the ECM between the power supply contact J1-11 and the return contact J1-12.Expected Result:The voltage measurement is 8.0 0.4 VDC.Results:
OK - The voltage measurement is 8.0 0.4 VDC. The voltage is correct. The ECM power supply is correct. Turn the key start switch and the disconnect switch to the OFF position. Install the wires and sockets that were removed from the J1 connector back into the original locations. Proceed to Test Step 2.
NOT OK - The voltage measurement is greater than 8.0 0.4 VDC. The ECM power supply is not correct.Repair: Prior to replacing an ECM, always contact the Technical Communicator for your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM requires replacement, refer to Troubleshooting, "Electronic Control Module (ECM) - Replace".STOPTest Step 2. CHECK THE SENSORS
Turn the key start switch and the disconnect switch to the ON position.
One at a time, disconnect the Track Speed Sensors from the machine harness.
After disconnecting each sensor, check the status of the CID 0041 FMI 04 diagnostic code.Expected Result:The CID 0041 FMI 04 diagnostic code is no longer active.Results:
OK - The CID 0041 FMI 04 diagnostic