GM Service Manual Online
For 1990-2009 cars only

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Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

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.

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

Are all of the turn signals and indicators inoperative?

Go to Step 5

Go to Step 4

4

Are only the turn signal indicators inoperative?

Go to Step 12

Go to Step 7

5

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

Does the test lamp illuminate?

Go to Step 6

Go to Step 22

6

  1. Turn OFF the ignition.
  2. Connect a test lamp between the battery positive voltage circuit of the turn signal/hazard flasher module and ground circuit of the turn signal/hazard flasher module.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 10

Go to Step 23

7

  1. Turn OFF the ignition.
  2. Disconnect the inoperative turn signal bulb.
  3. Connect a test lamp between the turn signal lamps supply voltage circuit of the inoperative turn signal bulb and the ground circuit of the inoperative turn signal bulb.
  4. Turn ON the inoperative turn signal.

Does the test lamp flash ON and OFF?

Go to Step 21

Go to Step 8

8

Test the turn signal lamps supply voltage circuit of the inoperative turn signal bulb for a high resistance, an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 31

Go to Step 9

9

Test the ground circuit of the inoperative turn signal bulb for a 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 31

Go to Step 10

10

  1. Turn OFF the ignition.
  2. Disconnect the turn signal/multifunction switch.
  3. Connect a test lamp between the ignition 1 voltage circuit of the turn signal/multifunction switch and ground.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 11

Go to Step 24

11

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

Does the test lamp illuminate?

Go to Step 18

Go to Step 15

12

Are the outside rear view mirror turn signal indicators inoperative?

Go to Step 13

Go to Step 14

13

  1. Turn OFF the ignition.
  2. Disconnect the outside rear view mirror turn with the inoperative turn signal indicator.
  3. Connect a test lamp between the turn signal lamps supply voltage circuit of the inoperative turn signal indicator and the ground circuit of the inoperative turn signal indicator.
  4. Turn ON the ignition, with the engine OFF.
  5. Turn ON the turn signal with the inoperative turn signal indicator.

Does the test lamp flash ON and OFF?

Go to Step 17

Go to Step 16

14

  1. Turn OFF the ignition.
  2. Remove the inoperative turn signal indicator bulb.
  3. Connect a test lamp between the turn signal lamps supply voltage circuit of the inoperative turn signal indicator bulb and the ground circuit of the inoperative turn signal indicator bulb.
  4. Turn ON the ignition, with the engine OFF.
  5. Turn ON the turn signal with the inoperative turn signal indicator.

Does the test lamp flash ON and OFF?

Go to Step 20

Go to Step 16

15

Test the cornering lamp supply voltage circuit of the inoperative turn signal for a 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 31

Go to Step 19

16

Test the turn signal lamps supply voltage circuit of the inoperative turn signal indicator for a 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 31

Go to Step 25

17

Inspect for poor connections at the harness connector of the outside rear view mirror with the inoperative turn signal indicator. 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 31

Go to Step 26

18

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 in Wiring Systems.

Did you find and correct the condition?

Go to Step 31

Go to Step 29

19

Inspect for poor connections at the harness connector of the turn signal/multifunction 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 31

Go to Step 28

20

Inspect for poor connections at the inoperative turn signal indicator bulb. 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 31

Go to Step 27

21

Inspect for poor connections at the inoperative turn signal bulb. 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 31

Go to Step 30

22

Repair the open, high resistance or short to ground in the turn signal/hazard flasher module battery positive voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

23

Repair the open or high resistance in the turn signal/hazard flasher module ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

24

Repair the open or short to ground in turn signal/multifunction switch ignition 1 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

25

Repair the open in the ground circuit of the inoperative turn signal indicator. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

26

Replace the outside rear view mirror with the inoperative turn signal indicator. Refer to Outside Rearview Mirror Glass Replacement in Doors.

Did you complete the replacement?

Go to Step 31

--

27

Replace the inoperative turn signal indicator bulb. Refer to Instrument Cluster Bulb Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 31

--

28

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

Did you complete the replacement?

Go to Step 31

--

29

Replace the turn signal/hazard flasher module. Refer to Hazard Lamp Flasher Replacement .

Did you complete the replacement?

Go to Step 31

--

30

Replace the inoperative turn signal bulb.

Did you complete the replacement?

Go to Step 31

--

31

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2