Horn Switch Test

NOTE:

SRS components are located in this area. Review the SRS component locations (see COMPONENT LOCATION INDEX ), and precautions and procedures (see PRECAUTIONS AND PROCEDURES ) before doing repairs or servicing.
Check for a blown No. 10(20A) fuse in the under-hood fuse/relay box. If it is blown, check for a faulty horn relay (built in the relay circuit board) (see POWER RELAY TEST ).

Remove the steering column covers (see SIDE DEFOGGER VENT TRIM REMOVAL/INSTALLATION ).
Disconnect cable reel connector A (20P) (A) from the cable reel (B).

Fig 1: Cable Reel With A (20P) Connector End View
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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.
Remove the jumper wire from cable reel connector A (20P).
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).
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 (see DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL AND INSTALLATION ).
Reconnect cable reel connector A (20P) to the cable reel, then remove the driver's airbag assembly (see DRIVER'S AIRBAG REPLACEMENT ).
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 (see CABLE REEL REPLACEMENT ).
Disconnect the cable reel connector C (20P) (A).

Fig 2: Cable Reel C (20P) Connector End View
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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).
Fig 3: Checking Cable Reel Connector C (20P) Terminal And Terminal (T9) For Continuity
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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.