Horn Switch: Testing and Inspection

Horn Switch Test

NOTE:

- SRS components are located in this area. Review the SRS component locations, precautions and procedures Service and Repair before doing repairs or servicing.
- Check for a blown No. 10 (20 A) fuse in the under-hood fuse/relay box. If it is blown, check for a faulty horn relay (built in the relay circuit board).

1. Remove the steering column covers Service and Repair.

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





3. Connect cable reel connector A (20P) terminals No. 1 and No. 2 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 cable reel connector A (20P).

5. Check for continuity between cable reel connector A (20P) terminal No. 2 and body ground. There should 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 (G405).

6. Measure the voltage between cable reel connector A (20P) terminal No. 1 and body ground. There should be battery voltage.

- If there is battery voltage, replace the horns.
- If there is no voltage, repair an open in the wire, or faulty driver's MICU; replace the driver's under-dash fuse/relay box.

7. Reconnect cable reel connector A (20P) to the cable reel, then remove the driver's airbag assembly Driver's Airbag Replacement.

8. Connect cable reel connector C (20P) terminals No. 11 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, repair open in the wire, or replace the cable reel Service and Repair.

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






10. Check for continuity between terminal (T9) and cable reel connector C (20P) terminal No. 12. 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 terminal (T9).





11. Check for continuity between cable reel connector C (20P) terminal No. 11 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 open in the wire, or replace the cable reel subharness.