FAN AS 3787650 - Caterpillar

Illustration 1 g01123610
Left Extender Glow Plug RelayThis diagnostic code is recorded when the ECM reads the current of the left extender glow plug relay as above normal (short to ground). The nominal coil resistance of the relay is approximately 360 ohms.The possible causes of this diagnostic code are:
The energize circuit for the relay is shorted to ground.
The relay is malfunctioning.
The ECM has failed. This is unlikely.System Response:The results of this diagnostic code are:
The burner diagnostic lamp that is located below the screed walkway will be ON.
The ECM will not initiate a burner ignition cycle for the left extender burner when this diagnostic code is active.Note: Ensure that the diagnostic code CID 928 FMI F06 for the relay is on hold and that the red diagnostic code present indicator on the conveyor ECM display is ON.Test Step 1. Check Relay
Turn the key start switch to the ON position.
Observe the status of the red conveyor ECM diagnostic code present indicator (ON or OFF).
Disconnect the relay from the relay socket.Expected Result:The conveyor ECM diagnostic code present indicator should turn OFF when the relay is removed from the socket.Results:
OK - The conveyor ECM diagnostic code present indicator does turn OFF when the relay is removed from the relay socket.Repair: The circuit is correct. The relay is malfunctioning. Replace the relay. Stop.
NOT OK - The conveyor ECM diagnostic code present indicator does not turn OFF when the relay is removed from the relay socket. Proceed to Test Step 2.Test Step 2. Check Relay Energize Circuit For Short To GroundThe relay remains disconnected from the relay socket.
Turn the key start switch to the OFF position.
Disconnect the machine harness connectors J1 and J2 from the ECM.
At the ECM machine harness connector, measure the resistance from the energize signal circuit at connector contact J2-19 (wire P812-YL) to all possible sources of ground. The possible ground sources are connector contacts J1-2, J1-5, J1-7, J1-15, J1-16 and J2-3.Expected Result:Each resistance should measure greater than 5000 ohms.Results:
OK - Each resistance measurement is greater than 5000 ohms. Proceed to Test Step 3.
NOT OK - One or more of the resistance measurements is less than 5000 ohms.Repair: There is a short in the machine harness for the left extender glow plug relay circuit. The short is between the energize signal circuit (wire P812-YL) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness. Stop.Test Step 3. Check To See If Diagnostic Code Remains
Clean the contacts of the harness connectors.
Reconnect all harness connectors and the relay.
Turn the key start switch to the ON position.
Enter burner service mode 3 on the conveyor ECM three digit display. Clear all inactive diagnostic codes.
Operate the machine.
Check to see if the CID 928 FMI F06 diagnostic code for the relay is active (red diagnostic code present indicator ON).Expected Result:The CID 928 FMI F06 diagnostic code for the relay is not active.Results:
OK - The CID 928 FMI F06 diagnostic code for the relay is not active. The machine harness and the ECM