GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Upfitter Provision Schematics in Wiring Systems

Connector End View Reference: Lighting Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Verify that the roof beacon lamp is always on.

Does the roof beacon lamp operate normally?

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

Go to Step 3

3

Disconnect the roof beacon relay.

Does the roof beacon lamp turn off?

Go to Step 4

Go to Step 6

4

  1. Reconnect the roof beacon relay.
  2. Disconnect the roof beacon switch.

Does the roof beacon lamp turn off?

Go to Step 7

Go to Step 5

5

Test the hazard switch signal circuit of the roof beacon switch for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

6

Repair the hazard flasher signal circuit of the roof beacon relay for a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 9

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7

Replace the roof beacon switch.

Did you complete the replacement?

Go to Step 9

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8

Replace the roof beacon relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 9

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9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3