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

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Verify that the tail lamps are inoperative.

Do the tail lamps operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Inspect the appropriate fuse for the inoperative lamps in the body relay block.

Is the fuse open?

Go to Step 5

Go to Step 4

4

Test the inoperative bulb or tail lamp printed circuit board for an open or poor terminal contact. Refer to Circuit Testing .

Did you find a condition?

Go to Step 7

Go to Step 6

5

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

Did you complete the repair?

Go to Step 8

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6

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

Did you complete the repair?

Go to Step 8

--

7

Replace the defective bulb or tail lamp printed circuit board. Refer to Tail Lamp Bulb Replacement or Tail Lamp Circuit Board 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