GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you review the symptom list?

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Go to Step 2

Go to Symptoms

2

Inspect the RADIO BATT fuse for an open.

Is the RADIO BATT fuse open?

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Go to Step 11

Go to Step 3

3

Inspect the RADIO fuse for an open.

Is the RADIO fuse open?

--

Go to Step 12

Go to Step 4

4

  1. Disconnect the radio harness connectors.
  2. Using a test lamp, backprobe between the radio harness connector C1 terminal 10 and ground.

Does the test lamp light?

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Go to Step 5

Go to Step 10

5

Using a test lamp, backprobe between the radio harness connector C1 and terminal 10 and terminal 5.

Does the test lamp light?

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Go to Step 6

Go to Step 7

6

  1. Using a test lamp, backprobe between the radio harness connector C1 terminal 9 and terminal 5.
  2. Turn the ignition switch to the RUN position.

Does the test lamp light?

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Go to Step 8

Go to Step 9

7

Repair a poor connection or open in circuit 351.

Is the repair complete?

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Go to Step 13

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8

Replace the radio. Refer to Radio Replacement .

Is the repair complete?

--

Go to Step 13

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9

Repair the poor connection or open in circuit 43.

Is the repair complete?

--

Go to Step 13

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10

Repair a poor connection or open in circuit 640.

Is the repair complete?

--

Go to Step 13

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11

Repair a short to ground in circuit 640.

Is the repair complete?

--

Go to Step 13

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12

Repair a short to ground in circuit 43.

Is the repair complete?

--

Go to Step 13

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13

Operate the system in order to verify the repair.

Did you correct the condition?

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Go to Symptoms

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