Repair Broken Or Missing Horn Contacts On 1970’s Ford F-Series Trucks
By Aric Waldron
I started out with a horn button missing all electrical parts. The previous owner had removed the internals, presumably because they didn’t work, and replaced them with a dash mounted button. Since my horns worked I knew the relay was fine, so I decided to make my own contacts rather than pay $100 for a new horn button assembly.
The track in the plastic horn button is 9/16″ wide, so I cut four pieces from a .020″ copper plate I found at a craft store. 2 aprox. 3″x9/16″ and 2 aprox 2″x9/16″. I then soldered a long wire on one end of each contact.
The contacts were made into buttons by a piece of double sided sticky tape approximately 1″x9/16″. The placement of the tape will allow the contacts to spring open after being pressed. I glued the contacts into the plastic horn assembly with weather strip adhesive, as it is removable and non-conductive. Double sided sticky tape would have made the button too tall possibly causing the rubber cover to press the button permanently.
The contact wires are then connected in such a way as to complete the circuit when either button is pressed. I connected both top contacts to each other, and then connected both bottom contacts to each other.
The bullet connectors allow easy attachment to the wires from the horn contacts. The positive connection in the right picture is an insulated ¼” female spade connector, and the ground is a fuel line spring clamp. It happens to fit nicely in the groove on the steering shaft, is cheap, and is held firmly by spring pressure.
Don’t forget that the horn relay grounds through the steering shaft and steering box to the frame. My ground wire was missing, so I installed a 5″ wire with terminal connectors across the steering coupler(a.k.a. rag joint). The final product looks perfectly stock and works well. The horn does not blow in the center position, but that could be remedied with a third button if desired.