GM Service Manual Online
For 1990-2009 cars

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

1

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

Go to Step 2

Go to Symptoms - Lighting Systems

2

  1. Place the turn signal switch in the LEFT TURN position.
  2. Place the turn signal switch in the RIGHT TURN position.

Do the turn signal lamps operate properly?

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

Go to Step 3

3

  1. Disconnect the hazard lamps flasher.
  2. Probe the battery positive voltage circuit of the hazard lamps flasher with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 9

4

Connect a test lamp between the battery positive voltage circuit of the hazard lamps flasher and the hazard lamps flasher ground circuit.

Does the test lamp illuminate?

Go to Step 5

Go to Step 10

5

  1. Connect a 20 amp fused jumper wire between the battery positive voltage circuit of the hazard lamps flasher and the hazard flasher signal circuit of the hazard lamps flasher.
  2. Place the turn signal switch in the LEFT TURN position.

Do the left turn lamps illuminate?

Go to Step 7

Go to Step 6

6

  1. Leave the fused jumper wire connected.
  2. Disconnect the turn signal switch.
  3. Probe the hazard flasher signal circuit of the turn signal switch with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 11

7

Inspect for poor connections at the hazard lamps 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 14

Go to Step 12

8

Inspect for poor connections at the turn signal 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 14

Go to Step 13

9

Repair an open, high resistance, or short to ground in the battery positive voltage circuit of the hazard lamps flasher. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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10

Repair an open or high resistance in the hazard lamps flasher ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

--

11

Repair an open, high resistance, or short to ground in the hazard flasher signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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12

Replace the hazard lamps flasher.

Did you complete the replacement?

Go to Step 14

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13

Replace the turn signal switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3