GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the license lamps are inoperative.

Do the license lamps operate normally?

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

Go to Step 3

3

Is the left tail lamp inoperative also?

Go to Step 5

Go to Step 4

4

Inspect the inoperative bulbs/sockets for open filaments or poor terminal contact.

Does any lamp have an open filament or poor terminal contact?

Go to Step 7

Go to Step 6

5

Repair the short to ground in the license lamp supply voltage circuit or left tail lamp tail supply voltage circuit or . Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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6

Repair the open or high resistance in the license lamps supply voltage circuit or ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 8

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7

Replace the inoperative bulb or repair/replace the socket. Refer to Wiring Repairs in Wiring Systems or Rear License Lamp Replacement .

Did you complete the repair?

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