GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you review the radio/audio system operation and perform the necessary inspections?

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Go to Step 2

Go to Symptoms

2

Verify that the radio display does not dim with the IP dimmer switch.

Does the radio display dim normally?

--

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

Go to Step 3

3

  1. Disconnect the radio connector.
  2. Turn the headlamp switch to the PKLP position.
  3. Turn the instrument panel, (IP) dimmer switch to a mid-range position.
  4. Connect a test lamp from CKT 1220 (GRY) at radio connector cavity F4 to ground.

Does the test lamp light?

--

Go to Step 4

Go to Step 5

4

Service the radio. Refer to Radio Replacement .

Is the service of the radio complete?

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Go to Step 6

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5

Locate and repair the open in CKT 1220 (GRY) between the radio and splice S205. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the repair complete?

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Go to Step 6

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6

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3