GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Inspect the T/SIG fuse.

Is the fuse open?

--

Go to Step 2

Go to Step 3

2

Repair a short to ground in one of the following circuits:

    • CKT 539
    • CKT 1508

Is the repair complete?

--

Go to Exterior Lights System Check

--

3

  1. Turn the ignition switch to the RUN position.
  2. Use a test lamp in order to backprobe between C201 terminal A2 and ground.

Did the test lamp light?

--

Go to Step 5

Go to Step 4

4

Repair the following conditions in CKT 539:

    • A faulty connection
    • An open circuit

Is the repair complete?

--

Go to Exterior Lights System Check

--

5

Use a test light in order to backprobe between connector C201 terminal E1 and ground.

Does the test light illuminate?

--

Go to Step 7

Go to Step 6

6

  1. Replace the turn signal switch.
  2. Inspect the system.

Is the repair complete?

--

Go to Exterior Lights System Check

--

7

Use a test light to backprobe the hazard lamp/turn signal flasher between connector terminal A1 and connector terminal B2.

Does the test light illuminate?

--

Go to Step 9

Go to Step 8

8

Repair the following conditions, as needed:

    • A faulty connection or an open in CKT 1508
    • A faulty connection or an open in CKT 1450 between B2 and ground

Has the repair been made?

--

Go to Exterior Lights System Check

--

9

  1. Turn the turn signal switch to the ON position.
  2. Use a test light in order to backprobe the hazard lamp/turn signal flasher connector between terminal C1 and ground.

Is the test light flashing?

--

Go to Step 11

Go to Step 10

10

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

Has the repair been made?

--

Go to Exterior Lights System Check

--

11

  1. Turn the turn signal switch to the ON position.
  2. Use a test light in order to backprobe the turn signal switch harness connector C201 terminal A4 to ground.

Is the test light flashing?

--

Go to Step 6

Go to Step 12

12

Repair the faulty connection or the open in CKT 16.

Has the repair been made?

--

Go to Exterior Lights System Check

--