Component Tests and General Diagnostics

HORN

Any diagnosis of the Horn system should begin with the use of a scan tool and the appropriate Diagnostic Service Manual.

Refer to the appropriate wiring information.

WARNING: Disable the airbag system before attempting any steering wheel, steering column, seat belt tensioner, side airbag or instrument panel component diagnosis or service. Disconnect and isolate the negative battery (ground) cable. Wait two minutes for the airbag system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the airbag system. Failure to follow these instructions may result in accidental airbag deployment and possible serious or fatal injury.

The horn system is separated into two parts: Horn switch input and the horn relay output.

- Using a scan tool, check to see if the Body Control Module senses the horn switch input. If the input is not OK, then check the wiring between the horn switch and the BCM.
- Using a scan tool, actuate the horn relay. If the relay activates, then check the wiring/fuse from the Power Distribution Center (PDC) to the horns.