GRAPPLE AR 1112377 - Caterpillar

Illustration 1 g02475693
Connections of the Ride Control Head End Check Valve solenoid
This diagnostic code is associated with the Ride Control Head End Check Valve solenoid. The FMI 03 diagnostic code is activated when the ECM detects an above normal voltage of the solenoid circuit. The following conditions could cause this diagnostic code to be activated:
The energize circuit of the solenoid is shorted to another voltage source.
The ECM has failed. This condition 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 and clear these diagnostic codes when the original diagnostic code has been corrected. Test Step 1. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID FOR A SHORT
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the machine harness connector from the solenoid. Disconnect the machine harness connectors J1 and J2 from the ECM.
At the machine harness connectors for the ECM, measure the resistance from contact J1-59 (wire A958-WH(White)) to all of the other contacts that are used in the J1 and J2 connectors for the ECM. Expected Result:Each resistance measurement is greater than 5000 ohms. Results:
YES - Each resistance measurement is greater than 5000 ohms. The resistance measurement does not indicate a short in the machine harness. Proceed to Test Step 2.
NO - Each resistance measurement is not greater than 5000 ohms. There is a short in the machine harness. Repair: The short is between wire A958-WH(White) and the circuit that has a low resistance measurement.For information on testing for short circuits and finding short circuits, refer to Testing and Adjusting, "Wiring Harness (Short Circuit) - Test". Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE OPERATION OF THE ECMThe disconnect switch and the key start switch remain in the OFF position. The machine harness connectors for the solenoid and the ECM remain disconnected.
At the machine harness connector J1 for the ECM, use a 151-6320 Removal Tool to remove the solenoid wire A958-WH(White) and the socket at contact J1-59 from the harness connector.
Reconnect the machine harness J1 and J2 connectors to the ECM.
Turn the disconnect switch and the key start switch to the ON position.
Observe the status of the active CID 3280 FMI 03 diagnostic code. Expected Result:The CID 3280 FMI 03 diagnostic code is no longer active. A CID 3280 FMI 05 diagnostic code is now active.Results:
YES - The CID 3280 FMI 03 diagnostic code is no longer active. A CID 3280 FMI 05 diagnostic code has become active after the solenoid circuit is disconnected. The ECM has responded