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 RR tail lamp is inoperative.

Do the tail lamps operate normally?

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

Go to Step 3

3

Place the Headlamp Switch in the PARK position and connect a test lamp from ground to terminal B of the inoperative bulb socket. 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 open, high resistance, or short to ground in CKT 2609 (BRN/WHT). 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 the test lamp between terminal B and terminal G of the inoperative bulb socket. 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 the open or high resistance in the ground CKT 1350 (BLK) or 2250 (BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 8

Go to Step 7

7

Replace the inoperative bulb.

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