The Ford Barn - Shocking horn!

That is an issue that has been reported before here on the Barn. Don't remember the cause at the moment!

From supereal post:

"Early horn circuits were simply a connection to a battery source, and other side to a switch, usually a horn button or ring on the steering wheel. Horns draw a lot of current, so a relay was added. This produced a side effect of creating a slight shock from the collapse of the relay coil to tingle the user. Then a resistance wire was added to reduce or eliminate the shock. Next to the starter, the horn(s) often draw a a heavy current."

petehoovie posted this

This thread from the EFV8 Club Site:

Discussion Topic: Horn Button Shocks -- page: 1 2

joe b 08-26-2015 @ 7:53 AM reply profile send p.m.
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I noticed my steering wheel on my '41 was a bit loose. I tightened it and now I notice my horn button shocks me. I have to be grounded such as resting my left arm on the door sill. It is more of a tingle than a profanity causing shock. What should I check?

deluxe40 08-26-2015 @ 9:05 AM reply profile send p.m.
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I had a '50 Ford that did that. I kept thinking there were bugs on my arm. The wire that runs up the steering column has a low current from the horn relay that is looking for ground. When you push the button, you ground the back side to the steering wheel engaging the relay and causing the horn to honk. There must be a short between the contacts on the back side of the button and the front of the button that you touch with your hand.

joe b 08-26-2015 @ 9:49 AM reply profile send p.m.
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Thanks deluxe. I put the horn wire back where it was. I will check it's location. May need a bit of electrical tape.

Old Henry 08-26-2015 @ 10:26 AM reply profile send p.m.
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The horn ring in my 47 used to tingle my arm resting on the window seal. I replaced the horn wire from the engine compartment connection with the stock resistor style wire and it went away.

Available at C&G here: http://cgfordparts.com/ufolder/cgcat...&sp=Search+%23

Or at Mac's here: http://www.macsautoparts.com/ford_me...rn+button+wire

This message was edited by Old Henry on 8-26-15 @ 5:01 PM
joe b 08-26-2015 @ 12:42 PM reply profile send p.m.
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Thanks for this Henry. It is inexpensive enough to give it a try. Will report back when installed.

supereal 08-28-2015 @ 8:31 PM reply profile send p.m.
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The horn relay acts like a little ignition coil. When the button makes contact and pulls the relay, the relay coil is charged. When the button is released, the magnetic field in the relay collapses and the "spark" discharges to the horn button or ring, giving a shock if you hand is on the button. Many manufacturers used a resistance wire from the steering wheel to the relay to prevent the shock. You can do the same with a one ohm resistor in series with the horn button wire.