GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you review the exterior lighting operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Lighting Systems

2

   • 

Probe the park lamp circuit at the connector that it is inoperative from upfitter connector or tractor trailer receptacle, with a test lamp that is connected to a good ground.

   • 

Place the headlamp switch in the PARK or HEADLAMP position.

Does the test lamp illuminate?

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

Go to Step 3

3

Do the vehicle's park lamps operate properly?

Go to Step 4

Go to Park Lamps Inoperative

4

Repair an open or short to ground in the park lamp voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 5

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5

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3