1955 Ford Part 41: Horn Wiring and Sound Test

Updated: Dec 27, 2019


Horn Wiring and Sound Test

Back many months ago I had disassembled the horns (both the Lo and Hi units), cleaned them up, re-painted the bodies, and installed them on the car. At that time both of them were bench tested and were found to be working properly. Now the question would be, "Can we get these things wired up properly?"

A couple of things to note would be these: 1. The car has been upgraded from 6 volt to a 12 volt system; 2. The steering column, wheel, and horn ring are from a 1956 Ford not a 55 (love the deep dish, three spoke look); 3. All original wiring had been discarded during tear down (frayed, dry-rotted insulation) knowing that a new harness would have to be made or purchased; 4. The main concern in my opinion would be the grounding of each component (horn ring, relay, and finally the horns). Like most horn systems of its day, the mid 50's horns used a relay switch to actuate the horns. The horn ring on the steering wheel grounded the circuit to the relay, thus giving power to the horns to sound off.

Since the horns were installed and bench tested it was time to get to work. First up was to place a brand new horn wire down through the center of the steering shaft.

The insulation for this length of wire is unusually thicker than most of the other insulation found in original wiring. This is so that the horn wire (or the grounding wire that goes to the horn relay) will be strong enough to be pushed down through the center of the hollow steering shaft without bunching up as it ends up at the bottom of the steering gear assembly.

The above photo shows the business end of the horn wire that carries the ground to the relay when the horn ring is pressed down to the column. Just a suggestion if you are doing this operation - make sure things do not get bound up as you re-assemble the horn ring to the column. The photo below shows how the wire should be sitting in the steering shaft before reassembly of the horn ring. You do not have to remove the steering wheel for this operation. I had the wheel removed at this time for other wiring operations under the dash and to gain access through the speedometer hole in the dash to get to other wiring.

You can tell in the photo below that finding the end of the wire after it has come through the steering gear can be quite difficult. Even in this picture where the end is identified it is still hard to see.

This end was pulled out of the steering gear to take up the slack and then in the video below you can see what I did to test the grounding action of the horn ring to make sure I could proceed to the next step with confidence.

Thankfully things went well and I could move on to wiring up the relay. The relay sits on the driver's side inner fender and has three terminals (H for horn, B for Battery, and G for ground). The relay also needs to be grounded itself by means of its metal/metal contact to the fender and hardware. I went a little further with that step and made sure one of its sheet metal screws were wired to a well-known ground. 12 gauge wire was used to connect the horns to the horn relay and 14 gauge was used for the ground. 10 gauge wire used to connect the battery to the horn relay. It should be obvious, but we will state it here - make sure you use a hot lead that is NOT from your ACC or IGN post on your ignition switch. You want the horn to sound whether or not the key is in the switch, so basically just make sure you have live lead that is hot 100% of the time the battery is connected.

And the results...

I am not sure what will be next - the floor insulation is halfway installed and I have already begun looking at the headlight and taillight wiring. Until next time...

#horn #relay

90 views

© 2019 by Daniel Jessup