Diagnosis And Testing - Horn Switch
To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbags, airbag curtains, knee blocker, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect the Intelligent Battery Sensor (IBS)/negative battery cable assembly from the negative battery post, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.
Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin out information and location views for the various wire harness connectors, splices and grounds.
- Remove the Driver Airbag (DAB) from the steering wheel. Refer to AIR BAG, DRIVER, REMOVAL .
- Disconnect the steering wheel wire harness connector from the horn switch wire harness connector.
- With the horn switch plate released, check for continuity between the two terminals in the horn switch pigtail wire harness connector. There should be no continuity. If OK, go to Step 4. If not OK, replace the ineffective horn switch plate (DAB) unit.
- With the horn switch plate depressed, check for continuity between the two terminals in the horn switch pigtail wire harness connector. There should now be continuity. If OK, go to Step 5. If not OK, replace the ineffective horn switch plate (DAB) unit.
- Check the steering wheel wire harness for shorts or opens between the horn switch connector and the clockspring connector. If not OK, repair or replace the steering wheel wire harness as required.