GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference : Radio/Audio System Schematics

Connector End Views Reference: Entertainment Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Operate all of the steering wheel controls.

Do all of the steering wheel controls operate properly?

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

Go to Step 3

3

Test the radio on signal circuit for a short to ground or open. 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 4

4

Caution: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling . Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs.

  1. Test the resistance of the steering wheel control switches.
  2. Press the steering wheel control switches to the correct function, one at a time, and compare the measured values to those shown.

Are the measured resistances approximately equal to the specified values?

Volume Up: 1.2K ohms

Volume Down: 1.56K ohms

Mode: 1.9K ohms

Mute: 2.38K ohms

Seek Up: 3.1K ohms

Seek Down: 4.28K ohms

Seek Type: 6.65K ohms

Pre-Set: 13.6K ohms

Go to Step 5

Go to Step 7

5

Test the steering wheel controls signal circuit for a short, high resistance or an open. 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

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

Did you find and correct the condition?

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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 Connector Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 10

Go to Step 8

8

Replace the appropriate steering wheel radio control. Refer to Steering Wheel Control Switch Assembly Replacement .

Did you complete the replacement?

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Go to Step 10

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9

Replace the radio. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

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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