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

Connector End View Reference: Master Electrical Component List

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Cover the ambient light sensor.
2. Turn ON the ignition, with the engine OFF.
3. Rotate the headlamp switch to the defeat position and release.

Do the headlamps turn OFF as expected?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

1. With the scan tool, observe the Headlamp Off Switch parameter.
2. Turn ON the ignition, with the engine OFF.
3. Rotate the headlamp switch to the defeat position and release.

Does the parameter switch from Inactive to Active while the headlamps or daytime running lamps (DRL) remain illuminated?

Go to Step 6

Go to Step 4

Test the headlamp switch headlamps OFF signal, circuit of the headlamp switch for the following:

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 5

Inspect for a poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 7

Inspect for a poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 9

--

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 9

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3