Diagnostic Test
- INTERMITTENT CONDITION
- Turn the ignition on.
- With the scan tool, clear all FCM DTCs.
- Turn the Headlamps on.
- With the scan tool, read the DTC information.
Does the scan tool display B1634-LEFT HI BEAM CONTROL CIRCUIT HIGH?
Yes
- Go to step 2
No
- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
- LEFT HIGH BEAM BULB
- Turn the ignition off.
- Inspect the Left High Beam Bulb Assembly.
Is the inoperative bulb OK?
Yes
- Go to step 3
No
- Replace the inoperative bulb in accordance with the Service Information.
- Perform the BODY VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
- (L33) HIGH BEAM CONTROL CIRCUIT OPEN
- Turn the ignition off.
- Disconnect the FCM C2 harness connector.
- Measure the resistance of the (L33) High Beam Control circuit.
Is the resistance above 5.0 Ohms?
Yes
- Repair the open in the (L33) High Beam Control circuit.
- Perform the BODY VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
No
- Replace the FCM in accordance with the Service Information.
- Perform the BODY VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .