Horn Switch: Testing and Inspection

Horn Switch Test

NOTE:

- SRS components are located in this area. Review the SRS component locations Locations, precautions and procedures Service and Repair before doing repairs or servicing.
- Check for a blown No. 11 (15 A) fuse in the main under-hood fuse box. If it is blown, check for a faulty horn relay (built in the relay control module) Power Relay Test.

1. Remove the steering column covers Service and Repair.

2. Disconnect the dashboard wire harness 20P connector (A) from the cable reel (B).





3. Connect dashboard wire harness 20P connector terminals No. 2 and No. 3 with a jumper wire. The horns should sound.

- If the horns sound, go to step 7.
- If the horns do not sound, go to step 4.

4. Remove the jumper wire from the dashboard wire harness 20P connector.

5. Check for continuity between dashboard wire harness 20P connector terminal No. 3 and body ground. There should be continuity.

- If there is continuity, go to step 6.
- If there is no continuity, repair an open or high resistance in the wire, or poor ground (G501).

6. Measure the voltage between dashboard wire harness 20P connector terminal No. 2 and body ground. There should be battery voltage.

- If there is battery voltage, check for continuity between the under-hood fuse/relay box and the horns. If there is continuity, replace the horns. If there is no continuity, repair an open in the wire.
- If there is no battery voltage, repair an open in the wire, or faulty relay control module; replace the under-hood fuse/relay box.

7. Reconnect the dashboard wire harness 20P connector to the cable reel, then remove the driver's airbag assembly Driver's Airbag Replacement.

8. Connect cable reel subharness 20P connector terminals No. 10 and No. 12 with a jumper wire. The horns should sound.

- If the horns sound, go to step 9.
- If the horns do not sound, replace the cable reel Service and Repair.

9. Disconnect the cable reel subharness 20P connector (A).






10. Check for continuity between ground terminal (T801) and cable reel subharness 20P connector terminal No. 10. There should be continuity.

- If there is continuity, go to step 11.
- If there is no continuity.
- An open in the wire, replace the cable reel subharness.
- Poor ground terminal connection (T801).





11. Check for continuity between cable reel subharness 20P connector terminal No. 12 and horn switch positive terminal 1P. There should be continuity.

- If there is continuity, check or adjust the installation of the driver's airbag assembly and the horn switch plate or replace the driver's airbag assembly.
- If there is no continuity, repair an open in the wire, or replace the cable reel subharness.