CHARGER GP-BTR 5273206 - Caterpillar

Illustration 1 g00948415
Test Step 1. CHECK THE HARNESS
Remove the backup alarm relay.
Turn the key start switch and the disconnect switch to the ON position.Expected Result:The backup alarm is OFF.Results:
YES - The backup alarm is OFF. Proceed to Test Step 2.
NO - The backup alarm is still active. The wire 321-BR is shorted to + battery voltage in the machine harness.Repair: Repair the machine harness or replace the machine harness. Stop.Test Step 2. CHECK THE BACKUP ALARM RELAY
Turn OFF the key start switch and the disconnect switch.
Replace the backup alarm relay with one of the other relays.
Turn ON the key start switch and the disconnect switch.Expected Result:The backup alarm is active.Results:
OK - The backup alarm is still active. Proceed to Test Step 3.
NOT OK - The backup alarm is inactive.Repair: The backup alarm relay has failed. Replace the backup alarm relay. Stop.Test Step 3. CHECK THE OUTPUT OF THE ECM
Turn OFF the key start switch and the disconnect switch.
At the ECM, remove the wire C936-GY from contact 17 of the machine harness.
Turn ON the key start switch and the disconnect switch.Expected Result:The backup alarm is active.Results:
OK - The backup alarm is still active. The wire C936-GY is shorted to + battery voltage in the machine harness.Repair: Repair the machine harness or replace the machine harness. Stop.
NOT OK - The backup alarm is inactive.Repair: It is unlikely that the ECM has failed. Exit this procedure and perform the entire procedure again. If the cause of the failure is not found, replace the ECM. See Troubleshooting, "Electronic Control Module (ECM) - Replace". Stop.