GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Horn Schematics

1

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

Go to Step 2

Go to Symptoms - Horns

2

Verify the fault is present.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step 3

3

Remove the horn relay.

Did the horn stop sounding?

Go to Step 4

Go to Step 5

4

Important:: The horn switch circuit is part of the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement in SIR.

To disable the SIR, system refer to SIR Disabling and Enabling in SIR.

With the horn relay still removed, test the switch signal circuit for continuity to ground. Refer to Circuit Testing in Wiring Systems.

Is ground present?

Go to Step 6

Go to Step 7

5

Repair the short to voltage in the horn supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and complete the repair?

Go to Step 8

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6

Repair the short to ground in the horn relay switch signal circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and complete the repair?

Go to Step 8

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7

Replace the horn relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3