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

  1. Remove the DRL relay from the underhood relay center.
  2. Measure the resistance from pin B8 to pin A7 of the DRL relay.

Is the resistance less than the specified value?

5 ohms

Go to Step 3

Go to Step 8

3

Inspect CKT 359 (PPL) for an open between the left high beam headlamp and the DRL relay. Refer to Testing for Continuity in Wiring Systems.

Is CKT 359 OK?

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Go to Step 4

Go to Step 6

4

Inspect CKT 11 (LT GRN) for an open between the left high beam headlamp and the connector C104. Refer to Testing for Continuity in Wiring Systems.

Is CKT 11 OK?

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Go to Step 5

Go to Step 6

5

Inspect CKT 711 (DK GRN/WHT) for an open between the connector C104 and the underhood fuse block. Refer to Testing for Continuity in Wiring Systems.

Is CKT 711 OK?

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Go to Step 7

Go to Step 6

6

Repair the open in the appropriate circuit. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 9

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7

Repair the open in CKT 750 (BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 9

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8

Replace the DRL relay.

Is the repair complete?

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Go to Step 9

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9

Operate the system in order to verify the repair. Did you correct the condition?

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System OK.

Go to Step 2