Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

1. Place the ignition switch in the OFF position.
2. Apply the park brake.
3. Place the headlamp switch in the OFF position.
4. Turn ON the ignition, with the engine OFF.
5. Place the turn signal switch in the RH ON position.
6. Place the turn signal switch in the LH ON position.

Do the front turn signals operate properly?

Go to Step 3

Go to Turn Signal Lamps and/or Indicators Inoperative

1. Release the park brake.
2. Apply a bright incandescent light to the sunload sensor assembly.
3. Place the turn signal switch in the OFF position.

Do the front turn signals lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 4

Is the park brake indicator in the instrument panel cluster (IPC) ON?

Go to Brake Warning Indicator Always On in Hydraulic Brakes

Go to Step 5

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Apply a bright incandescent light to the sunload sensor assembly.
4. With a scan tool, observe the Right and Left Sunload Sensor parameters in the HVAC system data display.

Does the scan tool indicate that the right and left Sunload Sensor parameters are between 50-60 counts?

Go to Step 7

Go to Step 6

Test the ambient light sensor signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and SIR/SRS Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

Replace the sunload sensor assembly. Refer to Sun Load Sensor Replacement in HVAC Systems - Automatic.

Did you complete the replacement?

Go to Step 10

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Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 10

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2