GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you Review the system operation?

--

Go to Step 2

Go to Symptoms

2

  1. Using a test light, backprobe between connector C205 terminal A to ground.
  2. Turn the ignition switch on.

Is the test light on?

--

Go to Step 4

Go to Step 3

3

Repair poor connection or open in circuit 43.

Is the repair complete?

--

Go to Step 15

--

4

  1. Disconnect C205.
  2. Connect a DMM between C205 (female side) terminal A and terminal C.
  3. Press each of the left steering wheel control buttons one at a time.

Are all the resistances approximately equal to the specified values?

    • Volume Up: 1270ohms
    • Volume Down: 1564ohms
    • Source: 1912ohms
    • Mute: 2387ohms
    • Seek Up: 3102ohms
    • Seek Down: 4282ohms
    • Scan: 6652ohms
    • AM/FM 13632ohms

Go to Step 8

Go to Step 5

5

  1. Disconnect the left radio control switch.
  2. Connect a DMM between the left radio control switch pigtail harness connector terminal A and terminal C.
  3. Press each of the left steering wheel control buttons, one at a time.

Are all the resistances approximately equal to the specified values?

    • Volume Up: 1270ohms
    • Volume Down: 1564ohms
    • Source: 1912ohms
    • Mute: 2387ohms
    • Seek Up: 3102ohms
    • Seek Down: 4282ohms
    • Scan: 6652ohms
    • AM/FM 13632ohms

Go to Step 7

Go to Step 6

6

Replace the left radio control switch. Refer to Steering Wheel Control Switches Replacement for service procedure.

Is the repair complete?

--

Go to Step 15

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7

Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement in SIR for service procedure.

Is the repair complete?

--

Go to Step 15

--

8

  1. Using a test light, backprobe between the radio harness connector terminal E6 to ground.
  2. Turn the ignition switch on.

Is the test light on?

--

Go to Step 9

Go to Step 10

9

Repair short to B+ on circuit 1796.

Is the repair complete?

--

Go to Step 15

--

10

Using a DMM, measure the resistance between the radio harness connector terminal E6 and ground.

Is the resistance measured same as the specified value?

Go to Step 12

Go to Step 11

11

Repair short to ground in circuit 1796.

Is the repair complete?

--

Go to Step 15

--

12

Test for poor connection or open in circuit 1796.

Did you find a poor connection or open in circuit 1796?

--

Go to Step 13

Go to Step 14

13

Repair poor connection or open in circuit 1796.

Is the repair complete?

--

Go to Step 15

--

14

Service the radio. Refer to Radio Replacement for service procedure.

Is the repair complete?

--

Go to Step 15

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15

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 1