GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you review the system operation and perform the necessary inspections?

--

Go to Step 2

Go to Symptoms - Entertainment

2

  1. Turn the ignition to the RUN position.
  2. Turn on the radio.
  3. Attempt to operate the radio functions using the steering wheel controls.

Do the steering wheel controls operate the radio functions?

--

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

Go to Step 3

3

Turn the radio on.

Are all of the radio functions operating normally from the radio?

--

Go to Step 4

Go to Step 5

4

  1. Disconnect connector C217.
  2. Measure the resistance with a DMM, probing between C217 (female side) terminal A and terminal C while pressing each of the steering wheel radio control buttons. Refer to Circuit Testing in Wiring Systems.
  3. Compare the resistance values to the chart following the diagnosis table.

Are the resistance values approximately equal?

--

Go to Step 6

Go to Step 7

5

  1. Disconnect the radio connector C3.
  2. Inspect the signal circuit of the steering wheel controls for a short to battery voltage or a short to ground. Refer to Circuit Testing , Wiring Repairs or Connector Repairs in Wiring Systems.

Did you find and repair a short?

--

Go to Step 10

Go to Step 9

6

Test for and repair an open or a poor connection in the signal circuit of the steering wheel controls. Refer to Circuit Testing or Testing for Intermittent Conditions and Poor Connections and Wiring Repairs or Connector Repairs in Wiring Systems.

Did you find and repair an open or a poor connection?

--

Go to Step 10

Go to Step 9

7

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.

Inspect the SIR coil for an open or a poor connection.

Did you find repair an open or a poor connection?

--

Go to Step 10

Go to Step 8

8

Replace the steering wheel controls. Refer to Steering Wheel Control Switches Replacement .

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 3

Controls

Value

VOL (UP)

1270ohms

VOL (DOWN)

1564ohms

PLAY

1912ohms

MUTE

2387ohms

SEEK (UP)

3102ohms

SEEK (DOWN)

4282ohms

AM/FM

6652ohms

PRESET

13632ohms