CUTTING EDGE 2K3601 - Caterpillar

Illustration 1 g03809979
Schematic of Back Up Alarm Relay
This diagnostic code is associated with the Backup Alarm Relay. The backup alarm relay is controlled by the ECM through an ON/OFF output driver. The FMI 05 diagnostic code means the ECM has energized the output for the relay and the current for the relay circuit is below normal.The conditions that could cause this diagnostic code to activate are listed below:
The relay has failed.
The energize circuit of the relay has an open or a bad connection in the machine harness.
The ECM has failed. The failure of the 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 meet the following requirements: clean, secure and 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 cause other diagnostic codes to be activated. Ignore these created diagnostic codes and clear the diagnostic codes when the problem has been corrected.Note: Use a calibrated digital multimeter for the measurements in this procedure.System Response:The backup alarm is off.Test Step 1. Check The Relay
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector from the relay.
At the harness connector for the relay, connect a jumper wire between contact 85 (wire 331-OR(Orange)) and contact 86 (wire 112-PU(Purple)).
Turn the disconnect switch and the key start switch to the ON position.
Observe the status of the active CID 144 FMI 05 diagnostic code. Expected Result:The active CID 144 FMI 05 diagnostic code is no longer active when the key start switch is turned ON. A CID 144 FMI 06 diagnostic code is now active.Results:
OK - The CID 144 FMI 05 diagnostic code is no longer active. A CID 144 FMI 06 diagnostic code becomes active when the key start switch is turned to theON position.Repair: The relay is causing the problem. Verify that the relay has failed by substituting a known good relay that is the same part number as the suspect relay. Replace the suspect relay.STOP
NOT OK - The jumper wire does not affect the status of the active CID 144 FMI 05 diagnostic code when the switch key is turned ON. The relay is not causing the problem. Proceed to Test Step 2.Test Step 2. Check The Relay Circuit For An Open The relay remains disconnected from the machine harness. The jumper wire remains connected between contact 86 and contact 85.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connectors J1 from the ECM for the Machine.
At the machine harness connector J1 for the ECM, measure the resistance between contact J1-23 (wire 331-OR(Orange)) and contact wire 112-PU(Purple). Expected Result:The resistance measurement is less than 5 ohms.Results:
OK - The resistance measurement is less than 5 ohms. The energize circuit