GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important: The horns may be turned off in feature customization. Refer to Feature Customization .

1

Did you perform the Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

  1. Remove the key from the ignition.
  2. Open any door.
  3. Lock the doors using the transmitter.
  4. Close the doors.

Does the horn chirp upon system arming?

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

Go to Step 3

3

  1. Disconnect the Body Control Module (BCM) connector C3.
  2. Connect a test lamp between battery voltage and the BCM connector C3 terminal C9. Refer to Circuit Testing in Wiring Systems.
  3. Press the horn switch on the steering wheel.

Does the test lamp illuminate?

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Go to Step 4

Go to Step 5

4

Test for and repair a poor connection at the BCM connector C3 terminal C9. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and repair a poor connection?

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Go to Step 7

Go to Step 6

5

Repair the open in circuit 28 between the BCM C3 terminal C9 and connector C216 terminal G. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 7

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6

Important: Perform the set up procedure for the body control system.

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

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Go to Step 7

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7

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3