GM Service Manual Online
For 1990-2009 cars only

Low/High Beam Headlamps Inoperative

Step

Action

Value(s)

Yes

No

1

Were you sent here from the DRL Diagnostic System Check?

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Go to Step 2

Go to DRL Diagnostic System Check

2

  1. Disconnect connector C209.
  2. Connect a DMM between connector C209 terminal W and ground.
  3. Measure the voltage at connector C209 terminal W.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 9

Go to Step 3

3

  1. Remove the HDLP Circuit Breaker #53 from the instrument panel electrical center.
  2. Connect a DMM between the instrument panel electrical center terminal A and ground.
  3. Measure the voltage at the instrument panel electrical center terminal A.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 4

Refer to Power Distribution

4

Connect a fused jumper (20 A) between the instrument panel electrical center terminals A and B which is used for the HDLP Circuit Breaker #53.

Does the 20 A fuse in the fused jumper open immediately?

--

Go to Step 5

Go to Step 6

5

Repair a short to ground in CKT 842.

Is the repair complete?

--

Go to DRL Diagnostic System Check

--

6

  1. Leave the jumper in place.
  2. Connect a DMM between the headlamp switch connector C209 terminal W and ground.
  3. Measure the voltage at the headlamp switch connector C209 terminal W.

Is the voltage within the specified values?

10.0-14.0V

Go to Step 8

Go to Step 7

7

Repair an open in CKT 842.

Is the repair complete?

--

Go to DRL Diagnostic System Check

--

8

Replace the HDLP Circuit Breaker #53.

Is the repair complete?

--

Go to DRL Diagnostic System Check

--

9

Replace the headlamp switch.

Is the repair complete?

--

Go to DRL Diagnostic System Check

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