How to Locate a Horn Relay

Automotive horn relays are a type of electrical switch used to transfer an electrical current to the horn. Since auto horns are wired through a harness to the battery, this type of switching is necessary to keep the battery's higher amperage current from flowing into the steering column to the horn ring or center horn pad of the steering wheel. Horn relays therefore are found in locations other than the steering column, and with a minimum of detective work or automotive electrical experience, the horn relay can be located by any adult in five to 10 minutes or less.

Things You'll Need

  • Flashlight
  • Flat-tip screwdriver
  • Check the owner's service manual first. Many owner's manuals have schematic drawings showing the location of the various fuses that protect the automobile's electrical systems and circuits. The horn relay is often found plugged into the fuse panel, and is marked as such on the panel ridge that surrounds it.

  • Check under the dashboard of the automobile to the left side of the steering column for the fuse panel and horn relay if an owner's manual is not available. Some vehicles have a snap-on plate that covers the fuse box from view. Look for this type of plate if the fuse panel is not immediately found under the dashboard.

  • Open the hood and check for a main fuse panel. This panel will have a snap-type cover that can be opened with a flat-tip screwdriver. The panel will be located on one of the two wheel wells or on the vehicle's firewall. The panel is elongated and contains the higher-amperage fuses.

  • Use a helper if the horn relay still can not be located. Have the helper blow the horn quickly. This will help you to locate the horn itself.

  • Disable the horn by pulling the plug-type connector from the horn. If the connection is held by a screw, use the screwdriver to loosen the screw and remove the wire. Protect the end of the wire with electrical tape to prevent it from grounding.

  • Depress the horn ring or center pad of the steering wheel to energize the horn circuit. This will cause an audible clicking sound that comes from the horn relay.

  • Follow the clicking sound directly to the relay.