Diagnostic Routine C

Diagnostic Routine C

Diagnostic Overview

One Or Both High Beams Are Inoperative

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

Normal Operation and Fault Conditions

REFER to High Beams .

Visual Inspection and Diagnostic Pre-checks

- Inspect the BCM (Body Control Module) fuse 74 (15A).

- Inspect the headlamp assembly for damage.

Pinpoint Test

1. CHECK THE LOW BEAM OPERATION

1. Ignition ON.

2. Check the operation of the low beams.

Do both low beams illuminate?







2. CHECK THE OPERATION OF THE WINDSHIELD WIPERS

1. Ignition ON.

2. Observe the windshield wipers while cycling the windshield wiper switch through various settings and then off.

Do the windshield wipers operate correctly?







3. CHECK FOR VOLTAGE TO THE HEADLAMP

1. Ignition OFF.

2. Disconnect: Inoperative Headlamp.

3. Ignition ON.

4. Place the headlamp switch in the HEADLAMPS ON position.

5. Activate the high beams using the multifunction switch.

6. Measure:





Is the voltage greater than 11 volts?







4. CHECK THE HIGH BEAM SUPPLY CIRCUIT FOR AN OPEN

1. Ignition OFF.

2. Place the headlamp switch in the OFF position.

3. Disconnect: BCM (Body Control Module) C2280D.

4. Measure:





Is the resistance less than 3 ohms?







5. CHECK THE MULTIFUNCTION SWITCH

1. Ignition OFF.

2. Install a new multifunction switch.

3. Ignition ON.

4. Place the headlamp switch in the HEADLAMPS ON position.

5. Activate the high beam function using the multifunction switch.

Do the high beams illuminate?







6. CHECK FOR CORRECT SASM (Steering Angle Sensor Module) OPERATION

1. Disconnect and inspect all SASM (Steering Angle Sensor Module) connectors.

2. 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

3. Reconnect the SASM (Steering Angle Sensor Module) connectors. Make sure they seat and latch correctly.

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

Is the concern still present?







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

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

2. 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

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

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

Is the concern still present?