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Diagnostic Routine D




Diagnostic Routine D

Diagnostic Overview

The Low Beams Are On Continuously

Refer to Wiring Diagram Set 85 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Low Beams .

REFER to Ballast .

Visual Inspection and Diagnostic Pre-checks

- Inspect the FLM (Front Lighting Control Module) for damage.

- Inspect the headlamp assembly and connector for damage.

Pinpoint Test

1. CHECK THE COMMUNICATION NETWORK

1. Ignition ON.

2. Using a scan tool, perform the FLM (Front Lighting Control Module) network test.

Does the FLM (Front Lighting Control Module) pass the network test?








2. CHECK FOR LIGHT SENSOR DTCs (Diagnostic Trouble Codes)

1. Review the DTCs (Diagnostic Trouble Codes) recorded from the BCM (Body Control Module) self-test.

Is DTC (Diagnostic Trouble Code) B1A85:11 or DTC (Diagnostic Trouble Code) B1A85:13 present?








3. CHECK THE FLM (Front Lighting Control Module) HEADLAMP SWITCH PID (Parameter Identification)

NOTE: Make sure the headlamp switch is aligned in the correct position when monitoring the PID (Parameter Identification).

1. Using a scan tool, view FLM (Front Lighting Control Module) PIDs (Parameter Identifications).

2. Using a scan tool, monitor the FLM (Front Lighting Control Module) LT_SW PID (Parameter Identification) while moving the headlamp switch through all positions.

Do the headlamp switch positions agree with the PID (Parameter Identification)?








4. CHECK THE BCM (Body Control Module) OUTPUT

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280E.

3. Ignition ON.

Does the left or right headlamp continue to illuminate?








5. CHECK FOR VOLTAGE TO THE HEADLAMP ASSEMBLY

1. Ignition OFF.

2. Disconnect: Illuminated Headlamp.

3. Ignition ON.

4. Measure:





Is any voltage present?








6. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect all BCM (Body Control Module) connectors.

3. Repair:

- corrosion (install new connector or terminals- clean module pins)
- damaged or bent pins- install new terminals/pins
- pushed-out pins- install new pins as necessary

4. Reconnect the BCM (Body Control Module) connectors. Make sure they seat and latch correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?