GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Place the headlamp switch in the OFF position.

Are the park lamps illuminated?

Go to Step 3

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

3

Disconnect the headlamp switch.

Are the park lamps illuminated?

Go to Step 4

Go to Step 5

4

Test the park lamp switch signal circuit and the park lamp relay control circuit of the body control module (BCM) for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 8

Go to Step 6

5

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

Did you find and correct the condition?

Go to Step 8

Go to Step 7

6

Repair a short to voltage in the park lamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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7

Replace the headlamp switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3