CUP 5P2503 - Caterpillar

Illustration 2 g06133130
Schematic of the Swing Brake solenoid for machine models with a 70 pin ECM connection.
This diagnostic code is associated with the Swing Brake solenoid. An FMI 05 diagnostic code means the ECM has determined the current of the solenoid circuit is below normal.Possible causes of this diagnostic code are:
The Swing Brake solenoid has failed.
An open wire in the Swing Brake solenoid circuits.
The Backup EPR Valve switch has failed, if applicable.
The Machine ECM may have failed, but this situation is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes now, but clear those codes after the original diagnostic code has been corrected.Note: Poor connections are often the cause of a problem in electrical circuits. Before performing this procedure, inspect all of the harness connectors involved in the circuit. Verify that all of the connections in the circuit are clean, secure, and in good condition. If a problem is found with any of the connections: correct the problem and verify that diagnostic code CID 0374 FMI 05 is still active, before performing the following procedures.System Response:Diagnostic code CID 0374 FMI 05 will be logged in the internal memory of the Machine ECM.Test Step 1. CHECK THE SOLENOID, THE ECM, AND THE CIRCUIT CONNECTIONS IN THE MACHINE HARNESS.
Turn the disconnect switch and the key start switch to the OFF position.
The Backup EPR Valve switch is in the OFF position, if applicable.
Disconnect the machine harness connector from the Swing Brake solenoid.
At the harness connector for the solenoid, place a jumper wire from contact 1 (K906-GN(Green)) to contact 2 (235-BK(Black)) on the connector.
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the CID 0374 FMI 05 diagnostic code.Expected Result:The CID 0374 FMI 05 diagnostic code remains active.Results:
YES - The CID 0374 FMI 05 diagnostic code remains active. The jumper wire did not change the code. The solenoid is NOT the cause of the problem.Repair: The machine harness has failed, the Backup EPR Valve switch has failed (if applicable), or the ECM may have failed.Go to Test Step 2.
NO - The CID 0374 FMI 05 diagnostic code is no longer active, and has been replaced by an active CID 0374 FMI 06 diagnostic code. The ECM has detected a valid diagnostic code.Repair: The ECM, and the harness connections, are correct. The solenoid has failed.Perform Test Step 1 again, to verify the solenoid failure. Replace the solenoid.Go to Test Step 5.Test Step 2. CHECK THE SOLENOID CIRCUITS FOR AN OPEN CONNECTION.
Turn the key start switch and the disconnect switch to the OFF position.
The harness connector remains disconnected from the Swing Brake solenoid.
The jumper wire that was placed into the Swing Brake solenoid harness connector during Test Step 1 remains in place.
The Backup EPR Valve switch is in the OFF position, if applicable.
Disconnect the J1 and the J2 machine harness connectors from the Machine ECM.
At the ECM harness connectors, measure the resistance from contact J2-23 (K907-BU(Blue)or K906-GN(Green))