GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the brake pedal is not pressed.

Are the stop lamps illuminated?

Go to Step 3

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

3

Disconnect the stop lamp switch.

Are the stop lamps illuminated?

Go to Step 4

Go to Step 5

4

Repair a short to battery positive voltage in the stop lamp switched voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 6

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5

Verify the stop lamp switch adjustment. Refer to Stop Lamp Switch Adjustment . If OK, replace the stop lamp switch. Refer to Stop Lamp Switch Replacement .

Did you complete the repair?

Go to Step 6

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6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2