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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Montana - 4WD 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Turn Signal Lamps and/or Indicators Inoperative

Turn Signal Lamps and/or Indicators Inoperative Domestic

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 - 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. Place the turn signal switch in the LH and RH ON position.

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 4

Go to Step 5

4
  1. Observe the turn signal lamps and indicators.
  2. Place the turn signal switch in the OFF position.
  3. Place the hazard switch in the ON position.

Do the hazard lamps operate?

Go to Step 6

Go to Step 23

5

Are only the turn signal indicators inoperative?

Go to Step 7

Go to Step 9

6

Using a test lamp connected to ground, backprobe the ignition 1 voltage circuit of the C201 connector that is fed by the T/SIG fuse.

Does the test lamp illuminate?

Go to Step 31

Go to Step 20

7
  1. Place the ignition switch in the OFF position.
  2. Disconnect the instrument panel cluster (IPC) connector.
  3. Place the ignition switch in the ON position.
  4. Place the turn signal switch in the appropriate on position.
  5. With a test lamp connected to ground, probe the turn lamp supply voltage circuit of the IPC connector.

Does the test lamp illuminate?

Go to Step 8

Go to Step 38

8

With a test lamp connected to battery positive voltage, probe the ground circuit of the IPC connector.

Does the test lamp illuminate?

Go to Step 29

Go to Step 37

9

Determine which of the following lamps are inoperative:

    • Front turn signal lamp LH or RH
    • Rear turn signal lamp LH or RH
    • Mirror turn signal lamp LH or RH, if equipped

Is a front turn signal lamp inoperative?

Go to Step 16

Go to Step 10

10

Is a rear turn signal lamp inoperative?

Go to Step 13

Go to Step 11

11
  1. Disconnect the inoperative mirror turn signal.
  2. Using a test lamp, probe between the supply voltage circuit and the ground circuit of inoperative mirror turn signal connector.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 28

Go to Step 12

12
  1. Using a test lamp connected to ground, probe the supply voltage circuit of inoperative mirror turn signal connector.
  2. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 35

Go to Step 36

13
  1. Remove the inoperative rear turn signal lamp bulb.
  2. Using a test lamp, probe between the supply voltage circuit and the ground circuit of inoperative turn signal lamp bulb socket.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 27

Go to Step 14

14
  1. Disconnect the tail lamp connector.
  2. Using a test lamp connected to ground, probe the turn signal supply voltage circuit of the tail lamp connector.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 15

Go to Step 22

15

Using a test lamp connected to ground, probe between the turn signal supply voltage circuit and the ground circuit of the tail lamp connector.

Does the test lamp illuminate?

Go to Step 28

Go to Step 34

16
  1. Disconnect the inoperative front turn signal lamp.
  2. Using a test lamp connected to ground, probe the supply voltage circuit of the inoperative front turn signal lamp.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 17

Go to Step 18

17

With a test lamp, probe between the supply voltage circuit and the ground circuit of the inoperative front turn signal lamp.

Does the test lamp illuminate?

Go to Step 27

Go to Step 33

18
  1. Place the ignition in the OFF position.
  2. Disconnect the daytime running lamps (DRL) control module connector.
  3. Turn the ignition to the ON position, with the engine OFF.
  4. Using a test lamp connected to ground, probe the turn signal switch signal circuit of DRL control module connector.
  5. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 19

Go to Step 21

19
  1. Connect a fused jumper between the turn signal switch signal circuit and the turn signal supply voltage circuit of the DRL control module. Refer to Circuit Testing in Wiring Systems.
  2. Place the turn signal switch in the RH or LH ON position.
  3. Using a test lamp connected to ground, probe the supply voltage circuit of the inoperative front turn signal lamp.

Does the test lamp illuminate?

Go to Step 30

Go to Step 32

20

Test for an open or high resistance in the ignition 1 supply voltage circuit of the turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 46

Go to Step 39

21

Test for an open, high resistance, or a short to ground in the turn signal switch signal circuit of the DRL control module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 46

Go to Step 31

22

Test for an open or high resistance in the turn signal supply voltage circuit of the inoperative rear turn signal. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 46

Go to Step 31

23
  1. Disconnect the turn signal/hazard flasher.
  2. Install a jumper between the turn signal/hazard flasher voltage supply circuit and the turn signal multifunction switch flasher circuit.
  3. Place the turn signal switch in to the TURN LEFT position.

Do the LEFT TURN signal lamps illuminate, non-flashing?

Go to Step 24

Go to Step 25

24

Test for a short to battery positive voltage, an open, or a poor connection in the ground circuit of the turn signal/hazard 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 46

Go to Step 40

25

Test for a short ground, an open, or a poor connection in the turn/hazard supply voltage circuit. 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 46

Go to Step 26

26

Test for a short to ground, an open, or a poor connection in the turn signal flasher signal circuit. 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 46

Go to Step 42

27

Inspect for poor connections at the inoperative turn signal lamp bulb socket. 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 46

Go to Step 44

28

Inspect for poor connections at the harness connector of the tail lamp or mirror turn signal. 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 46

Go to Step 43

29

Inspect for poor connections at the harness connector of the 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 46

Go to Step 45

30

Inspect for poor connections at the harness connector of the DRL control 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 46

Go to Step 41

31

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 46

Go to Step 42

32

Repair an open or high resistance in the supply voltage circuit of the front turn signal. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 46

--

33

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

Did you complete the repair?

Go to Step 46

--

34

Repair an open or high resistance in the ground circuit of the tail lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 46

--

35

Repair an open or high resistance in the ground circuit of the inoperative mirror turn signal. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 46

--

36

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

Did you complete the repair?

Go to Step 46

--

37

Repair an open or high resistance 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 46

--

38

Repair an open or high resistance in the supply voltage 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 46

--

39

Repair the short to ground in the ignition 1 supply voltage circuit of the turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 46

--

40

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

Did you complete the replacement?

Go to Step 46

--

41

Replace the DRL control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

Go to Step 46

 

42

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

Did you complete the repair?

Go to Step 46

--

43

Replace the inoperative turn lamp. Refer to the appropriate procedure:

    •  Power Mirror Replacement in Doors.

Did you complete the repair?

Go to Step 46

--

44

Replace the inoperative turn signal bulb.

Did you complete the repair?

Go to Step 46

--

45

Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

Go to Step 46

--

46

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Turn Signal Lamps and/or Indicators Inoperative Export

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 - 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 7

Go to Step 9

5
  1. Observe the turn signal lamps and indicators.
  2. Place the turn signal switch in the OFF position.
  3. Place the hazard switch in the ON position.

Do the hazard lamps operate?

Go to Step 6

Go to Hazard Lamps Inoperative

6

Using a test lamp connected to ground, backprobe the ignition 1 voltage circuit of the C201 connector that is fed by the T/SIG fuse.

Does the test lamp illuminate?

Go to Step 15

Go to Step 16

7
  1. Place the ignition in the OFF position.
  2. Disconnect the instrument panel cluster connector.
  3. Place the ignition in the ON position.
  4. Place the turn signal switch in the appropriate on position.
  5. Using a test lamp connected to ground, probe the turn lamp supply voltage circuit of the instrument panel cluster connector.

Does the test lamp illuminate?

Go to Step 8

Go to Step 25

8

Using a test lamp connected to battery positive voltage, probe the ground circuit of the instrument panel cluster connector.

Does the test lamp illuminate?

Go to Step 20

Go to Step 24

9

Is a rear turn signal lamp inoperative?

Go to Step 10

Go to Step 13

10
  1. Remove the inoperative rear turn signal lamp bulb.
  2. Using a test lamp, probe between the supply voltage circuit and the ground circuit of inoperative turn signal lamp bulb socket.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 18

Go to Step 11

11
  1. Disconnect the tail lamp connector.
  2. Using a test lamp connected to ground, probe the turn signal supply voltage circuit of the tail lamp connector.
  3. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 12

Go to Step 17

12
  1. Place the turn signal switch in the RH or LH ON position.
  2. Using a test lamp connected to ground, probe between the turn signal supply voltage circuit and the ground circuit of the tail lamp connector.

Does the test lamp illuminate?

Go to Step 19

Go to Step 23

13
  1. Turn the ignition to the OFF position.
  2. Using a test lamp connected to ground, probe the supply voltage circuit of the inoperative turn signal lamp.
  3. Turn ON the ignition, with the engine OFF.
  4. Place the turn signal switch in the RH or LH ON position.

Does the test lamp illuminate?

Go to Step 14

Go to Step 15

14
  1. Place the turn signal switch in the RH or LH ON position.
  2. Using a test lamp connected to ground, probe between the turn signal supply voltage circuit and the ground circuit of the inoperative turn signal.

Does the test lamp illuminate?

Go to Step 18

Go to Step 22

15

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

Did you find and correct the condition?

Go to Step 31

Go to Step 21

16

Test for an open or high resistance in the ignition 1 supply voltage circuit of the turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 31

Go to Step 26

17

Test for an open or high resistance in the turn signal supply voltage circuit of the inoperative rear turn signal. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 31

Go to Step 21

18

Inspect for poor connections at the inoperative turn signal lamp bulb socket. 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 tail lamp. 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 harness connector of the instrument panel 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 31

Go to Step 30

21

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 31

Go to Step 27

22

Repair an open or high resistance in the ground circuit of the inoperative turn signal. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

23

Repair an open or high resistance in the ground circuit of the tail lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

24

Repair an open or high resistance 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

--

25

Repair an open or high resistance in the supply voltage 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

Repair the short to ground in one of the ignition 1 supply voltage circuit of the turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 31

--

27

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

Did you complete the repair?

Go to Step 31

--

28

Replace the inoperative rear tail lamp assembly. Refer to Tail Lamp Assembly and /or Backup, Sidemarker, Stop, Turn Signal Bulb Replacement .

Did you complete the repair?

Go to Step 31

--

29

Replace the inoperative turn signal lamp bulb.

Did you complete the repair?

Go to Step 31

--

30

Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

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