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?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Verify that the LF turn signal lamp is inoperative.

Do the turn signal lamps operate normally?

--

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

Go to Step 3

3

  1. Turn the ignition switch to the RUN position. Do not start the engine.
  2. Move the Multi Function Switch ( turn signal switch) to the LH TURN position.
  3. Inspect the other turn signal/marker bulbs at both ends on the same side of the vehicle for proper operation.

Are the other lamps illuminating properly?

--

Go to Step 4

Go to Symptoms

4

Use a test lamp from ground to terminal A of the inoperative bulb socket. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 5

5

Locate and repair the open, high resistance or short to ground in CKT 1414 (LT BLU/WHT) or CKT 2114 (LT BLU). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 9

--

6

Use a test lamp between terminal A and terminal G of the inoperative bulb socket. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 8

7

Replace the inoperative bulb.

Is the repair complete?

--

Go to Step 9

--

8

Locate and repair the open or high resistance in CKT 150 (BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 9

--

9

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3