I recently got my 1960 F100. The day it showed up neither the horn nor the high beams worked. I spoke to the previous owner and he said that they do work occasionally but it seemed related to moisture. It's been in dry storage for a few weeks and both seem to work now.
Is it a bad ground on each of those circuits? If so, does anyone know where the factory ground location is? The low beam never seems to be a problem- would that use the same ground as the high beam?
If that's not the problem are there any other ideas?
Thanks.

 

I don't believe they are related unless you call checking your wiring for a good connection. I would be sure and check out the floor switch for high to low. Electical is always fun. Sound like test light time.

 

Hi Deyo,

Yes you are right about the headlight wiring. It is a dedicated ground wire that is sheet metal screwed onto the headlight bucket...if one beam is gounded then both are grounded. This sounds like the high beam switch is bad.

The horn circuit is grounded through the body of the horns themselves. It's hard to say what's going on. Moisture would tend to make bad grounds better not worse. But a hsort on the other hand could be caused by water on a bare wire. Could be corrosion in the horn relay or horns themselves, or the high bean switch.

J!

 

I agree with headlite switch solution. The horn can be as simple as corrosion between the horn and where it is bolted onto the body or maybe even loose at that place! The entire truck likes to have it's connections tight!

 

I agree with everyone that the light problems is most likely in the dimmer switch.You can check the voltage applied to the horns by using a test light or meter. Have someone push the horn button and see if you have power at the connection on the horn. Voltage there and no sound--bad ground. If no voltage--work backwards toward the firewall to horn relay and button/ring.

 

Thanks for the advice. I bought a new switch for short money so I'll see about that. As for the horn- the last time it wasn't working I could hear the relay click and had 12v at the horn. An hour later it worked. Probably a bad ground. I'll take it off and clean everything off.
Thanks.

 

Mine do that sometime too, and I have no explanation as to why. I'm thinking it might just be due to age.

My four trumpets in my 51 are all newly installed on a clean well grounded surface, new wiring, new relay, new horn button and innards. And about once every 50 honks it just "gets stuck."

J!