GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

Did you perform the Lighting Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Turn ON the hazard flashers.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step 3

3

  1. Turn ON the ignition with the engine OFF.
  2. Turn ON the turn signal.

Do the turn signals function properly?

Go to Step 4

Go to Turn Signal Lamps and/or Indicators Inoperative

4

  1. Turn OFF the turn signal.
  2. Turn OFF the ignition.
  3. Disconnect the turn/hazard flasher.
  4. Turn ON the hazard flasher switch.
  5. Connect a test lamp between the turn/hazard module supply voltage circuit of the turn/hazard lamp flasher and a good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 5

5

Test the turn/hazard module supply voltage circuit of the turn/hazard lamp flasher for a short to ground, high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 6

6

Test the battery positive voltage circuit of the hazard warning switch for a short to ground, high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

7

Inspect for poor connections at the harness connector of the turn/hazard lamp flasher. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 9

8

Inspect for poor connections at the harness connector of the hazard warning switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 10

9

Replace the turn/hazard lamp flasher.

Did you complete the replacement?

Go to Step 11

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10

Replace the turn/hazard switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt or Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Standard.

Did you complete the replacement?

Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3