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Horn Switch: Testing and Inspection






DIAGNOSIS AND TESTING - HORN SWITCH

For complete circuit diagrams, 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 battery negative (ground) cable, then 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 take the proper precautions could result in accidental airbag deployment and possible personal injury.

1. Disconnect and isolate the battery negative cable.

2. Remove the steering column opening cover.

3. Check for continuity between the metal steering column jacket and a good ground. There should be continuity. If OK, go to STEP 4. If not OK, refer Steering Column for proper installation of the steering column.

4. Remove the driver side airbag module from the steering wheel. Disconnect the horn switch wire harness connectors from the driver side airbag module.




5. Remove the horn relay from the Junction Block (JB). Check for continuity between the steering column half of the horn switch feed wire (3) harness connector and a good ground. There should be no continuity. If OK, go to STEP 6. If not OK, repair the shorted horn relay control circuit to the horn relay in the Junction Block as required.

6. Check for continuity between the steering column half of the horn switch feed wire harness connector and the horn relay control circuit cavity for the horn relay in the Junction Block. There should be continuity. If OK, go to STEP 7. If not OK, repair the open horn relay control circuit to the horn relay in the Junction Block as required.

7. Check for continuity between the horn switch feed wire and the horn switch ground wire (2) on the driver side airbag module. There should be no continuity. If OK, go to STEP 8. If not OK, replace the faulty horn switch.

8. Depress the center of the driver side airbag module trim cover (5) and check for continuity between the horn switch feed wire and the horn switch ground wire on the driver side airbag module. There should now be continuity. If not OK, replace the faulty horn switch.