B1634

B1634-LEFT HI BEAM CONTROL CIRCUIT HIGH

B1634 - Left Hi Beam Control Circuit High:

WHEN MONITORED
With the Headlamps activated.

SET CONDITION
When the FCM detects a HIGH condition.

POSSIBLE CAUSES
- (L33) High beam control circuit shorted to B(+)
- Left high beam lamp
- Front control module

Diagnostic Test

1. INTERMITTENT CONDITION

Turn the ignition on.
With the Scan Tool, clear all FCM DTC's.
Turn the Headlamps on.
With the Scan Tool read the DTC information.

Q: Does the Scan Tool read: B1634-LEFT HI BEAM CONTROL CIRCUIT HIGH?

YES: Go To 2
NO: The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test

2. LEFT HIGH BEAM LAMP

Turn the ignition off.
Inspect the Left High Beam Lamp assembly for an open condition.

Q: Is the inoperative bulb OK?

YES: Go To 3.
NO: Replace the inoperative bulb.
Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test


3. (L33) HIGH BEAM CONTROL CIRCUIT






Turn the ignition off.
Disconnect the FCM C2 harness connector.
Measure the resistance of the (L33) Left High Beam Control circuit at the FCM.

Q: Is the resistance above 5.0 ohms?

YES: Repair the (L33) High Beam Control circuit for a short to battery condition.
Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Front Control Module (FCM).
Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test