My horn on my '66 CC/CS doesn't work. It has been updated from a 3 on the tree to C6 auto. With the AC system and CD player, the previous owner has done some butchering of the wiring. I have the '66 wiring diagram and shop manual on CD and have been working on it all day.

The horn itself is one problem - I apply 12v directly to the contact and it will blow only once in a while. I believe the diaphrams in these horns can get corroded and by some penetrating oil plus adjustments of the tuning screw they can start working again? Horn has good ground.

Started tracing wiring all the way back to the steering column. Continuity exists from the horn to the horn relay which has good 12v feed. Continuity from horn relay to firewall harness all the way into brass spring loaded contact on horn ring. From the diagrams I've seen, my steering wheel (which I took apart to clean and check out turn signal cam (wasn't broke! but needed lubing) and grease bearing sleeve) has everything except the spring which goes inbetween the horn button and steering wheel.

OK, so here's where I can't quite figure the circuit out. Usually the relay is used to switch in a higher current feed. So I'm assuming that when one pushes on the horn button, it sends voltage down to the horn relay which then kicks in the 12v line which comes straight over from the starter relay/battery to the horn. Yes, or No (like it is just a ground circuit completed in the horn button to the relay)? Second confusion point. I can't figure out the mechanism in the horn button to complete the circuit. Does the spring which is missing in my wheel actually provide part of the circuit to the horn button backside? When pressed on, does the side metal lip on the back of the horn button make contact with the metal plate where the steering shaft pokes through?

I think something else might be missing in my wheel. Using some wire to jump different parts of the wheel/horn and it did nothing - no continuity or 12v hot circuits detected.....................

Thanks,
dagger

 

dagger
The horn button completes the ground circuit for the relay which then routes power to the horns. The spring you refer to is needed for the horn button to work, it is the sliding contact, when turning, that when the horn button is depressed completes the ground. You should be able to ground the location where the spring contact fits and make the horns blow. If not then check relay and horns for proper function.

 

David,
Putt is right, your horn button to relay wire is a ground, so there is no readout when checking back to 12V source. But If you check to ground you should get 12V value.
FBp

 

David,
Putt is right, your horn button to relay wire is a ground, so there is no readout when checking back to 12V source. But If you check to ground you should get 12V value.
Yeah, while I'm at it, that thing with a spring & a copper wire inside is called a horn brush contact. The only other spring I know of is the one that keeps horn buton/ ring floating until it's depressed ot activate the relay & horn.

FBp

 

OK, that clears up one of the circuit issues I had - the horn button completes a grounding circuit - thanks! Now, on the actual function of the horn button: the metal spring (which is missing on my truck) encircles the steering shaft nut resting on the metal plate in the shifter column and the other end is on the middle of the metal disc on the back of the horn button. I believe the small spring loaded brass (copper?) contact is on the opposite side of this plate (or maybe not?). When I press one of the bars on the horn button and it tilts to that side, what is it suppose to come in contact with - it looks like the same metal plate the spring is on (and brass spring contact)? I can't see how this completes a grounding circuit.

Thanks again,
dagger

 

Finally verified horn relay works and traced the circuit all the way to the back side of the steering wheel. Nothing on the front side where the horn button twists on would complete the circuit. Took the wheel off again, checked everything and the small spring loaded brass contact - and then I saw the access hole to the front of the wheel. There is a non conductive tube there, and I must be missing another spring loaded contact that fits in there and completes the circuit when the horn button is depressed!

Thanks all for the replies. Now to find those 2 missing pieces and I should be good to go.

 

Okay David, let me try this. . . .

With horn button & spring off you're looking at hub of your steering wheel & 15/16" nut that retains strg wheel to steering shaft. On one side of hub is a hole 5/16ths" or 3/8ths" dia. It goes right thru wheel hub. Directly below it, under wheel is circular, flat brass ring going around the shaft, in same area where the T-Sig cams & trips etc are.

A phenolite or plastic bushing fits in hole in hub, insulating horn contact brush, which is installed flat brass end up, cylinderical, "barrel" end down riding on circular brass ring.

If you look under horn button you see 2 levels of steel plates. One is notched about 1 inch long & 1/4" wide along edge of it. It's a slightly curved cut out sort of notch.

This notched part should be placed over phenolite bushing & brush. When button w/ spring in position, is pushed & twisted about 1/6th it locks in place. If depressed the unnotched plate touches brass top creating a ground to activate relay which powers the horn, If "everybodys' home" it ought to blow.

That big spring under the horn button holds tension against horn button so it is not constantly grounded - or grounding out.

The grounding takes place through steering column, that's why there's a grounding lead across your rag joint so there's continuity to chassis through steering gear box.

Does that explain it awright for ya?

In re-reading, I see you push a lever down, so think horn "ring" where I say button

FBp

 

Thanks FBp - it all makes sense now. What was missing is this brush that goes through the phenolic bushing (besides the horn spring), and that was the missing "link" that kept me baffled when trying to figure out and trace the circuit.

OK, I will look to buy these 2 items (I know horn ring spring is available, not sure about the brush) or find a used parts source. That takes care of the horn - now to straighten out the wiring/lighting to the instrument cluster next

Cheers,
dagger

 

Just thought would mention there are 2 type horn button springs. The 'horn ring' spring is larger than the 'horn button' spring. Also, Mr. Mustang makes 64 thru 67 repro wire harnesses. Same wire codes and connectors. Replaced harnesses in 65, unfortunately, unable to find anyone who makes repro. dash harness. In case interested, the headlight harness runs about $100.

dave

 

A quick fix for a missing horn spring is to use the spring out of a ballpoint pen. I did it about 15 years ago in my 64 F100, and it is still working.

 

Drove up to Carolina-Classics today and Ricky had both the horn ring spring and the little spring brush. Installed and now I have 12V to the horn connector. The horn itself would only blow a little once in a while so I dumped the debris from the inside, soaked the inside with electrical contact cleaner, and then sprayed a little penetrating oil in there. Hooked the horn up to 12V and after turning the adjuster screw a few times she sounds loud and clear! Now to put a coat of paint on it and try to reinstall it (very tight fit!) and that's one job finished.

Next project.......

 

It's the little successful projects that give us the momentum to do the larger projects. Does your truck have only one horn or two?

 

Slick Repair dagger! Very Slick. . . . . . my Man!
Just like a pony car only bigger and better,huh? Easy to repair once one understands what is supposed to be there & why & how it is supposed to work.

I couldn't agree more with RalieghDad, it is the little things that encourage us to try the bigger things. Who knows what you'll accomplish next. Oh yeah, one of the great things about these great trux is they're not complex or over thought, but they're also far beyond "primitive" at the same time.

FBp!

 

Thanks guys - especially with the guidance on how the circuit and hardware were suppose to work. Ya, it's the little successes that do keep you going. Even my C6 with the stripped bolts has a painted pan, slightly longer bolts, and no fluid leaks now!

So, I jumped into my inside door handle not working/opening the door on the drivers side. Popped the door panel off expecting it to be like the mustang with the access hole behind it, and nope - lots of metal! Removed the bottom metal panel - here we go. Guess what - linkage and mechanisms for both door handle and window crank are OK. BUTT, somebody stripped both handles' inside teeth as well as the teeth on the door handle and window crank. They installed sheet metal screws where the set screws go to hold the handles on, but the door opener one is just spinning around. Man, I don't want to replace these units (nor have to spend the money to buy the replacements). I don't think just replacing the handles will suffice, so one alternative would be to somehow drill into the handles so that a set screw would anchor into them. However, I don't believe I can drill into them with hand drill. Hey, my vise grip on the door handle gear works just great I just hate finding crap like this.........

Might have to start a door handle/window crank thread now

Cheers,
dagger

 

You drove to Durham and didn't call to see if you could buy me lunch or something?

I have a pain in my heart now. sniff


John