GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Radio/Audio System Schematics

1

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

Go to Step 2

Go to Radio/Audio System Description and Operation

2

  1. Turn ON the ignition, with the engine OFF.
  2. Operate the radio using the steering wheel controls (SWC).

Does the radio operate normally with the steering wheel controls?

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

Go to Step 3

3

Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

  1. Disable the SIR. Refer to Disabling the SIR System in SIR.
  2. Remove the SIR assembly to expose the SWC connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Test the RAP fuse supply voltage circuit of the SWC connector for an open.

Did you find and correct the condition?

Go to Step 10

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Measure the resistance between the RAP fuse supply voltage circuit and the steering wheel controls signal circuit of the SWC connector attached to the SWC switches.
  3. Depress the following steering controls .
  4. • Volume Up
    • Volume Down
    • Mute
    • Seek Up
    • Seek Down
    • Preset

Do the resistance values change?

Go to Step 5

Go to Step 7

5

  1. Turn OFF the ignition.
  2. Disconnect the radio.
  3. Test the steering wheel controls signal circuit for a short, high resistance or an open.

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

Inspect for poor connections at the harness connector of the radio. Refer to Testing for Intermittent Conditions and Poor Connections and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

7

Inspect for poor connections at the harness connector of the steering wheel radio controls. Refer to Testing for Intermittent Conditions and Poor Connections and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

8

Replace the appropriate SWC switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 10

--

9

Replace the radio. Refer to Radio Replacement .

Did you complete the replacement?

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2