Horn Relay

Replace the horn relay on a 1970 AMC Rebel Machine to restore horn functionality.

Warnings

Tools required

Parts

• Horn relay × 1 — Use OEM specification or Standard Motor Products HR-106

Preparation

1. Ensure ignition is off and key is removed
2. Disconnect negative battery cable
3. Allow engine to cool if recently operated
4. Locate horn relay - typically mounted on firewall near brake master cylinder or on driver side inner fender panel

Procedure

1. 1

   Locate and identify horn relay
   Open hood and locate the horn relay on the firewall or inner fender panel. The relay is a small rectangular or cylindrical electrical component with multiple wire terminals. On 1970 AMC Rebel Machine, it is typically mounted near the brake master cylinder area on the firewall. Verify you have identified the correct relay by tracing the horn button wire from the steering column.
2. 2

   Document wire connections
   Before removing any wires, note the position and color of each wire connected to the relay terminals. Typical connections include: battery feed wire (usually heavy gauge red or orange), horn circuit wire from steering wheel (lighter gauge), ground wire, and output wire to horn(s). Take a photo or make a diagram if necessary.
3. 3

   Disconnect electrical connections
   Carefully disconnect all wires from the horn relay terminals. Some terminals may have push-on connectors that pull straight off, while others may have screw terminals that require loosening with a screwdriver. Use needle-nose pliers if connectors are tight. Keep wires separated to prevent confusion during reinstallation.
4. 4

   Remove mounting hardware
   Remove the mounting bracket bolt or screw securing the relay to the firewall or fender panel. The relay may be held by a single screw, clip, or bracket. Keep hardware for reinstallation.
5. 5

   Inspect and clean connections
   Examine all wire terminals for corrosion, damage, or burning. Clean terminals with wire brush or electrical contact cleaner if corrosion is present. Check wiring for fraying or damage. Replace any damaged terminals or wiring before installing new relay.
6. 6

   Install new horn relay
   Position the new horn relay in the mounting location and secure with original hardware. Ensure relay is firmly mounted and positioned to avoid contact with hot engine components or moving parts. Orient relay to match original installation position.
7. 7

   Reconnect electrical connections
   Reconnect all wires to the new relay terminals according to your documentation from Step 2. Ensure each connection is secure and properly seated. Double-check that battery feed, horn button circuit, ground, and horn output wires are all connected to correct terminals. Push-on connectors should click into place; screw terminals should be tightened firmly but not overtorqued.
8. 8

   Reconnect battery and test
   Reconnect the negative battery cable. Turn ignition to accessory position and test horn operation by pressing horn button on steering wheel. Horn should sound immediately with clear, strong tone. If horn does not sound, recheck all connections and verify relay orientation.

Reassembly

1. Verify all electrical connections are secure and properly routed away from hot or moving components
2. Ensure relay mounting is tight and relay cannot vibrate loose

Verification

• Test horn operation with engine off and ignition in accessory position - horn should sound when button is pressed
• Test horn with engine running to verify operation under normal conditions
• Verify no clicking or chattering from relay during horn activation
• Check that horn stops immediately when button is released

More procedures for this vehicle