LOCK 0T0018 - Caterpillar

Illustration 1 g01527312
Schematic of the Hook Free Fall Clutch Solenoid 2 CircuitThis diagnostic code is associated with the Hook Free Fall Clutch Solenoid 2 for the hook. The FMI 06 means that the ECM has determined that there is a short to ground in the solenoid circuit. The possible causes of this diagnostic code are listed:
The energize circuit of the solenoid is shorted to ground.
The solenoid has failed.
The ECM has failed. This is unlikely. Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 2952 FMI 06 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. CHECK THE SOLENOID.
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine.
Observe the status of the diagnostic code.
Disconnect the solenoid with the active diagnostic code from the machine harness. Expected Result:The FMI 06 changes to FMI 05 when the solenoid is disconnected.Results:
YES - The FMI 06 changes to FMI 05 when the solenoid is disconnected. The circuit is correct.Repair: The solenoid has failed. Replace the solenoid. Verify that the new solenoid corrects the problem.STOP
NO - The FMI 06 remains active. Proceed to Test Step 2.Test Step 2. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID FOR A SHORT TO GROUND.
Turn the key start switch and the disconnect switch to the OFF position.
The solenoid remains disconnected from the machine harness.
Disconnect the machine harness connector(s) from the ECM.
At the machine harness connector, measure the resistance from the signal contact J1-66 (wire A551-YL) to all contacts that are used in the machine harness connectors for the ECM. Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
OK - Each resistance measurement is greater than 5000 ohms. The machine harness is correct. Proceed to Test Step 3.
NOT OK - Each resistance measurement is not greater than 5000 ohms. There is a short in the machine harness. The short is between J1-66 (wire A551-YL) and the circuit with the low resistance measurement.Repair: Repair the machine harness or replace the machine harness. STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the harness connectors. Clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, corrosion, or chafing.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
Reconnect all harness connectors in order to make sure that the connectors are fully seated. Also, make sure that the clips for each connector are completely fastened.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Check the status of the CID 2952 FMI 06. Expected Result:The CID 2952 FMI 06 is active. Results:
YES - The CID 2952 FMI 06 is active. The diagnostic code has not been corrected.Repair: Check the circuit again. If the Caterpillar Electronic Technician