CYLINDER AS 5337800 - Caterpillar

Illustration 1 g02324393
Schematic of the "Quick Coupler Unlocking" SolenoidThis diagnostic code is associated with the "Quick Coupler Unlocking" Solenoid. The FMI 05 diagnostic code means that the ECM has detected a current reading for the solenoid circuit that is below normal.Conditions that could cause this diagnostic code to be activated are listed below:
The energize circuit of the solenoid is open.
The return circuit of the solenoid is open.
The solenoid has failed.
The switch panel has failed.
The ECM has failed. A failure of the Machine ECM is unlikely. Note: 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, that all connections are secure and that all connections are 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. Ignore these created diagnostic codes. Clear any created diagnostic codes after the original diagnostic code has been corrected.System Response:A Level 1 warning will be generated.Note: The resistance of the solenoid coil should be approximately 9 ohms at 20 °C (68.0 °F).Test Step 1. CHECK THE SOLENOID
Disconnect the solenoid from the machine harness.
At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire 780-PU) to contact 2 (wire 235-BK).
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the CID 1939 FMI 05 diagnostic code.Expected Result:The CID 1939 FMI 05 diagnostic code is no longer active. A CID 1939 FMI 06 diagnostic code becomes active when the jumper wire is connected.Results:
YES - The CID 1939 FMI 05 diagnostic code is no longer active. A CID 1939 FMI 06 diagnostic code becomes active when the jumper wire is connected. The solenoid has failed.Repair: Repeat this Test Step "CHECK THE SOLENOID" in order to verify the solenoid failure.Temporarily connect a new solenoid to the harness. Do not install the solenoid. Verify that the replacement solenoid has cleared the diagnostic code. If the code is no longer active, permanently install the new solenoid. Verify that there are no active diagnostic codes for the solenoid. Clear any logged diagnostic codes.STOP
NO - The CID 1939 FMI 05 diagnostic code remains active. The jumper wire does not affect the status of the active diagnostic code. The solenoid is not the cause of the problem. Proceed to Test Step 2.Test Step 2. CHECK THE CIRCUIT FOR AN OPENThe jumper wire that was installed in the previous Test Step remains in place.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness connector C2 from the switch panel.
At the machine harness connector C2 for the switch panel, measure the resistance from contact C2-5 (wire 780-PU) to contact C2-2 (wire 235-BK).
While observing the multimeter resistance measurement, wiggle the machine harness