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 in Wiring Systems

1

Did you perform the Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Place the ignition switch in the ON position.
  2. Place the turn signal switch in the LH ON position.
  3. Place the turn signal switch in the RH ON position.
  4. Determine if any of the turn signals or turn signal indicators are inoperative.

Are the turn signals and indicators operating properly?

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

Go to Step 3

3

Are all of the turn signals and indicators inoperative?

Go to Step 4

Go to Step 5

4

Press the hazard switch to the ON position.

Do all of the hazard lamps operate?

Go to Step 6

Go to Step 14

5

Are only the I/P turn signal indicators inoperative?

Go to Step 12

Go to Step 8

6

  1. Disconnect the turn signal switch.
  2. Install a jumper between the multifunction switch ground circuit and the left turn signal switch circuit.

Do the left turn signal lamps illuminate?

Go to Step 13

Go to Step 7

7

Test for an open, poor connection or a short to battery positive voltage in the ground circuit of the turn signal switch. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 14

8

Is only the hazard lamps inoperative?

Go to Hazard Lamps Inoperative

Go to Step 9

9

Are both the front and rear turn signal lamps inoperative on one side?

Go to Step 10

Go to Step 15

10

  1. Disconnect the turn signal switch.
  2. Install a jumper between the turn signal switch ground circuit and the inoperative side turn signal switch circuit.

Do the turn signal lamps illuminate?

Go to Step 13

Go to Step 11

11

Test for a poor connection, open or a short to battery positive voltage in inoperative turn signal switch circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 14

12

Important: Perform the setup procedure for the I/P.

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

Did you complete the replacement and the setup procedure?

Go to Step 20

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13

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

Is the replacement complete?

Go to Step 20

--

14

Important: After replacing the BCM, perform the setup procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Computer/Integrating Systems.

Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems.

Did you complete the repair?

Go to Step 20

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15

  1. Disconnect the inoperative turn signal lamp.
  2. Place the turn signal switch to the inoperative side.
  3. Using a test lamp connected to ground, probe the turn signal supply voltage circuit.

Does the test lamp flash?

Go to Step 16

Go to Step 18

16

Using a test lamp connected to the turn signal supply voltage circuit, probe the turn signal lamp ground circuit.

Does the test lamp flash?

Go to Step 19

Go to Step 17

17

Repair a poor connection, an open or a short to battery positive voltage in the ground circuit of the turn signal lamp. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

--

18

Test for a poor connection, open or a short to ground in the turn signal lamp voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 20

Go to Step 14

19

Replace the inoperative turn signal lamp. Refer to Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement and Tail/Turn Signal Lamp Replacement .

Did you complete the repair?

Go to Step 20

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20

  1. Connect all connectors and components that were previously disconnected.
  2. Verify that the turn signal lamps and indicators operate properly.

Does the turn signal lamps and indicators operate properly?

System OK

Go to Step 3