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

  1. Turn ON the ignition, with the engine OFF.
  2. Operate the turn signals.

Do the turn signal lamps and indicators operate properly?

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

Go to Step 3

3

Does only the turn signal indicator remain illuminated?

Go to Step 10

Go to Step 4

4

Do the turn signal lamps flash?

Go to Step 5

Go to Step 6

5

  1. Turn OFF the ignition.
  2. Disconnect the turn/hazard flasher module.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the appropriate turn signal input circuit and a good ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 9

6

  1. Turn OFF the ignition.
  2. Disconnect the turn/hazard flasher module.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the appropriate turn signal lamp supply circuit and a good ground.

Does the test lamp illuminate?

Go to Step 11

Go to Step 9

7

Test for a short to battery positive voltage in the appropriate turn signal input circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 8

8

Inspect for poor connections at the harness connector of 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 15

Go to Step 12

9

Inspect for poor connections at the harness connector of the turn/hazard flasher module. 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 15

Go to Step 13

10

Inspect for poor connections at the harness connector of the Instrument Cluster (IPC). 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 15

Go to Step 14

11

Repair a short to battery positive voltage in the appropriate turn signal lamp supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 15

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12

Replace the turn signal switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

Go to Step 15

--

13

Replace the turn signal/hazard flasher module. Refer to Hazard and Turn Signal Flasher Replacement .

Did you complete the replacement?

Go to Step 15

--

14

Replace the Instrument Cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2