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 left high beam headlamp is inoperative.

Do the headlamps operate normally?

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

Go to Step 3

3

  1. Disconnect the left headlamp high beam connector.
  2. Move the headlamp switch to the ON (HEAD) position.
  3. Move the multifunction switch to the HI BEAMS position.
  4. Connect a test lamp from ground to the left headlamp high beam supply voltage circuit at the bulb connector. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

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Go to Step 5

Go to Step 4

4

Locate and repair the open, high resistance or short to ground in the left headlamp high beam supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 8

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5

Connect a test lamp between the left headlamp high beam supply voltage circuit and CKT 524 (PPL) at the bulb connector. Refer to Circuit Testing in Wiring Systems.

Does the test lamp illuminate?

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Go to Step 7

Go to Step 6

6

Locate and repair an open or high resistance in CKT 524 (PPL). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 8

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7

Replace the left headlamp high beam bulb. Refer to Headlamp Replacement .

Is the repair complete?

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Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3