GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Turn ON the park lamps.

Do the clearance lamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Are the park lamps illuminated?

Go to Step 4

Go to Park, License, and Tail Lamps Inoperative

4

Are all clearance lamps inoperative?

Go to Step 7

Go to Step 5

5

Test the clearance lamp supply voltage and ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Inspect for poor connections at the harness connector of the clearance lamp. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Repair the interior park lamps supply voltage circuit of the clearance lamps for the following:

    • An open
    • A high resistance
    • A short to ground

Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 9

--

8

Replace the affected clearance/identification lamp. Refer to Roof Clearance Lamp Bulb Replacement or Roof Identification Lamp Bulb Replacement .

Did you complete the replacement?

Go to Step 9

--

9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3