GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting Systems Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the turn signal lamps are inoperative.

Do the turn signal lamps operate normally?

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

Go to Step 3

3

Inspect the TURN 20A fuse 10 in the IP fuse block.

Is the fuse open?

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Go to Step 12

Go to Step 4

4

  1. Turn the Ignition and Start Switch to the RUN position
  2. Using a test lamp to ground, backprobe connector C211 terminal A2 to ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

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Go to Step 6

Go to Step 5

5

Locate and repair the open in CKT 139 (PNK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 14

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6

  1. Activate the Multifunction Switch (Turn Signal Switch).
  2. Using a test lamp to ground, backprobe connector C211 terminal A3 to ground. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

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Go to Step 8

Go to Step 7

7

Replace the Multifunction Switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Standard or Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Is the repair complete?

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Go to Step 14

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8

Inspect for an open or high resistance in the following circuits. Refer to Circuit Testing in Wiring Systems.

    • CKT 1508 (LT BLU)
    • CKT 1697 (PPL)
    • CKT 1050 (BLK)

Was a problem found?

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Go to Step 9

Go to Step 10

9

Locate and repair the open or high resistance in one of the following circuits. Refer to Wiring Repairs in Wiring Systems.

    • CKT 1508 (LT BLU)
    • CKT 1697 (PPL)
    • CKT 1050 (BLK)

Is the repair complete?

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Go to Step 14

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10

  1. Disconnect C211.
  2. Place the Multifunction Switch (Turn Signal Switch) in the LH turn position.
  3. Test the Multifunction Switch (Turn Signal Switch) for continuity using a J 39200 Digital Multimeter (DMM) between C211 terminal A5 and terminal A7. Refer to Circuit Testing in Wiring Systems.

Is continuity present?

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Go to Step 11

Go to Step 7

11

Replace the turn signal lamp flasher.

Is the repair complete?

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Go to Step 14

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12

Inspect the following circuits for a short to ground. Refer to Circuit Testing in Wiring Systems.

    • CKT 139 (PNK)
    • CKT 1508 (LT BLU)
    • CKT 1696 (GRY) (Pickup)
    • CKT 1697 (PPL)
    • CKT 1414 (LT BLU/WHT)
    • CKT 1415 (DK BLU/WHT)
    • CKT 1418 (YEL/BLK)
    • CKT 1419 (DK GRN/WHT)

Was a problem found?

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Go to Step 13

Go to Step 11

13

Locate and repair the short to ground found in one of the following circuits. Refer to Wiring Repairs in Wiring Systems.

    • CKT 139 (PNK)
    • CKT 1508 (LT BLU)
    • CKT 1696 (GRY) (Pickup)
    • CKT 1697 (PPL)
    • CKT 1414 (LT BLU/WHT)
    • CKT 1415 (DK BLU/WHT)
    • CKT 1418 (YEL/BLK)
    • CKT 1419 (DK GRN/WHT)

Is the repair complete?

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Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3