Horn Switch Test

Remove the driver's dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ), and the driver's dashboard lower cover (see DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION ), then remove the steering column covers (see STEERING COLUMN REMOVAL AND INSTALLATION ).
Disconnect the 20P connector (A) from the cable reel (B).

Fig 1: Identifying Cable Reel And Horn 20P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Using a jumper wire, connect the No. 4 terminal of the dashboard wire harness (or combination switch wire harness)* 20P connector to body ground. The horns should sound.
*: '05 model

Fig 2: Connecting No. 4 Terminal Of 20P Connector To Body Ground Using A Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
- If the horns sound, go to step 4.
- If the horns don't sound, check these items:
  - No. 13 (15 A) fuse in the under-hood fuse/relay box
  - Relay control module in the under-hood fuse/relay box
  - Horns (see HORN TEST/REPLACEMENT )
  - An open in the wire
Reconnect the 20P connector (A) to the cable reel (B).

Fig 3: Identifying Cable Reel And 20P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove the driver's airbag assembly (see DRIVER'S AIRBAG REPLACEMENT ), and disconnect the horn switch 1P terminal (C) from the driver's airbag.
Check for continuity between the cable reel 20P connector No. 4 terminal and the horn switch 1P terminal. There should be continuity.
- If there is continuity, check the installation of the driver's airbag assembly and the steering wheel. If OK, replace the driver's airbag assembly.
- If there is no continuity, check these items:
  - Cable reel
  - An open in the wire
    
    Fig 4: Checking Continuity Between Cable Reel 20P Connector No. 4 Terminal And Horn Switch 1P Terminal
    Courtesy of AMERICAN HONDA MOTOR CO., INC.