GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: Radio/Audio System Schematics

1

Did you review the Radio/Audio System Description and Operation?

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Go to Step 2

Go to Symptoms - Entertainment

2

Tune the radio to a strong AM station and then tune to a strong FM station.

Is the radio reception clear?

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Go to Audio System Troubleshooting Hints

Go to Step 3

3

  1. Turn the radio on.
  2. Test for voltage on the antenna relay coil voltage circuit at the radio antenna module.

Does the voltage equal the specified value?

12 V

Go to Step 5

Go to Step 4

4

Test for an open or short to ground on the antenna relay coil supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 10

Go to Step 5

5

Test for an open or short to ground on the FM composite signal circuit. If the system is not equipped with this circuit, continue with the next step. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 10

Go to Step 6

6

Test for an open on the radio antenna module ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 10

Go to Step 7

7

Inspect the coaxial cable, between the radio and the radio antenna module.

If the cable is damaged, replace the coaxial cable. Refer to Radio Antenna Cable Extension Cable Replacement .

Did you find and correct the condition?

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Go to Step 10

Go to Step 8

8

  1. Inspect the connection between the rear window antenna grid and the radio antenna module, refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
  2. Inspect the connection between the front window antenna grid (if equipped) and the radio antenna module.
  3. If the connections are OK, replace the radio antenna module. Refer to Antenna Amplifier Replacement .

Did you find and correct the condition?

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Go to Step 10

Go to Step 9

9

  1. Inspect the radio connections, refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
  2. If the connections are OK, replace the radio. Refer to Radio Replacement .

Is the repair complete?

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Go to Step 10

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10

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2