GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition, with the engine OFF.
  2. Observe the turn signal lamps and indicators.
  3. Turn ON and OFF the right and left turn signal lamps.
  4. Turn OFF the ignition.

Do the turn signal lamps and indicators operate properly?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Are only the turn signal indicators always ON or flashing?

Go to Step 6

Go to Step 4

4

Test the supply voltage circuit of the always ON or flashing turn signal bulb or indicator for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 5

5

  1. Disconnect the turn signal/hazard flasher module.
  2. Connect a test lamp between the always ON or flashing turn signal switch signal circuit of the turn signal/hazard flasher module and a good ground.
  3. Turn OFF the always ON or flashing turn signal.

Does the test lamp illuminate?

Go to Step 7

Go to Step 8

6

  1. Disconnect the Instrument panel cluster (IPC).
  2. Connect a test lamp between the turn signal lamps supply voltage circuit of the always ON or flashing turn signal indicator and the IPC ground circuit.
  3. Turn OFF the always on or flashing turn signal indicator.

Does the test lamp illuminate?

Go to Step 9

Go to Step 12

7

Test the turn signal switch signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 11

8

Test the ignition 1 voltage circuit of the multifunction, turn signal switch for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 10

9

Test the turn signal lamps supply voltage circuit of the IPC for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 10

10

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

Did you find and correct the condition?

Go to Step 16

Go to Step 13

11

Inspect for poor connections at the harness connector of the multifunction, turn signal switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 14

12

Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

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 16

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14

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

Did you complete the replacement?

Go to Step 16

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15

Replace the IPC. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 16

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16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2