GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems in Lighting Systems.

2

  1. Turn the ignition to the ON position.
  2. Turn the headlamp switch to the ON position.

Are Both of the headlamps on?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Using a test lamp connected to a known good ground, backprobe the left headlamp low beam B+ feed circuit.

Does the test lamp turn on?

Go to Step 5

Go to Step 4

4

Repair a poor connection or an open in the left headlamp low beam B+ feed circuit.

Has the repair been made?

Go to Step 8

--

5

Using a test lamp, backprobe between the left headlamp low beam B+ feed circuit and the left headlamp low beam ground circuit .

Does the test lamp turn on?

Go to Step 6

Go to Step 7

6

Replace the left low beam headlamp.

Refer to Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement .

Has the repair been made?

Go to Step 8

--

7

Repair a poor connection or an open in the left headlamp low beam ground circuit.

Has the repair been made?

Go to Step 8

--

8

Operate the system in order to verify the repair.

Did you correct the condition?

Go to Diagnostic System Check - Lighting Systems

Go to Step 2