Strange Case of Overactive Horns

[magwakeenercew2jh]

Seems like the horn circuit is about the most simple one on our trucks.

Horn grounds itself and the + (green) goes thru the firewall at the fuse block and then under the dash to the horn relay. Three wires to the horn relay:
Red is always hot, the green that goes thru the firewall, and the black that grounds at the horn button after making it's way there via the banana-shaped
"Directional Signal Connection".

I've had the horn button fabbed and installed for a while, had the wiring harness (new) installed for a long while (like, a year). Although I haven't really been idling the motor much
because I'm running straight out of the headers for the time being, everything horn-related has worked well while it was at the shop ....and for the last week that she's been home.
I drove her home the 1/4 mile from the shop with open pipes just to get here. And, I've moved the truck in and out of the garage to do little stuff while I wait for the exhaust appointment.

But today, I started the truck and let it idol up to temp. the frigging horn started to honk. Because the last work was at the horn button, I pulled that off quickly and "un-grounded"
inside the steering wheel. Nope!!!!

Hoooooonnnnnnkkkk! Steady, neighbor raising, yelp from the horn. (And I live in the country)

I jumped out and pulled the green horn wire. Which sparked, showing me, if I didn't already know it, that it was getting juice with no jey on, no horn button pushed, nothin'

I waited about three minutes while I thought about it. Went and got the voltage tester light. Yup, drat'ed unwanted juice at the disconnected green wire.

Waited another three minutes or so, checked again. No juice at the green wire.

Re-connected the black ground wire at the column (horn button), connected the green wire at the horn. Pushed the horn button. "Honk!" Un-ground (un push) No honk.
Push the button. "Honk!" Cool. Just the way it's supposed to work.

Drove into the garage and let her idol for a couple of minutes. Shut down and got out and did a few things.

While I was about 100 feet from the truck....."Hoooooonnnnnnkkkkkk!"

I had to go pull the green wire. Tested for juice...of course, there was juice at the green wire. Waited until three minutes later, no juice.
So I connected the green wire again. Perfect honking again from the horn button.

I walked away.....Three minuted later, auto-honk again.

Relay? I've had a little problem at the fuse block since the build. Maybe a grounding there? It seems that would be less likely...Although next week my M&H fuse block
and under-dash harness will be here (All the rest of the harness' are new M &H), I suspect the horn relay. Obviously, the green is getting juice. Obviously, the red is hot to the relay.
I'm convinced that the horn button, ring, spring, etc. are not the culprit, as when all is working, the grounding starts and stops on "button command".....

Am I thinking straight on the horn relay? Can they fail in the "honking" position?

Any tips?

[Yooper truck]

I just had that problem too. I solved it last weekend. I had recently replaced the turning signal cam and this is where my problem originated.

When I tightened the cam in into place I didn't want to over torque it because it is plastic. However, it did need to be tightened a bit more as it caused the stalk for the turning signal to ride a bit higher. The turning stalk was then making occasional contact with the back of the plastic ring thing (for lack of a better term) that has the metal disk to continue the contact to the wiring. By tightening the cam the gap between the turning stalk and the metal disk/plastic ring thing increased so that it was no longer making contact.

I unplugged the wiring at the horns so I could diagnose it without repeatedly setting off the horn. You will hear a little click when it grounds, which is a whole lot better than jumping everytime the horn goes off.

I hope this helps.

[ChevLoRay]

Electrical problem.....LOL. Sounds like you're getting some good advice....or your truck is horny.

[magwakeenercew2jh]

Yooper...Thanks for the tip. I just went and checked. Unfortunately, your problem and my problem seem to
have different gremlin sources.

Did you have those "auto-pilot" features, too? Or was your "instant-on" related to the position of the steering wheel
or turn signal lever?

I didn't pull the steering wheel to check, but it seems that the turn signal cam in my tilt wheel allows more than enough
clearance that the turn signal stalk can't come in contact with *anything*.

Also, that three minute wait and then the juice turns off at the horn seems to make the fixes a little different.

It is obvious that the horn circuit is finding ground on an intermittent basis. Then "ungrounding" without so
much as a breath on anything by my chubby hands.....Uggg!

Mostly because of the on again, off again aspect of this deal, I'm still wondering if it could be in the horn relay itself.

[magwakeenercew2jh]

Originally Posted by ChevLoRay

Electrical problem.....LOL. Sounds like you're getting some good advice....or your truck is horny.

Like father, like son, I guess.

Ooof! That's sick...in a not-good way...

[Daner]

I had a car do that to me this summer on the way to a parade. Horn ring was broken and I couldn't get it to honk. Start driving to town and the horns would just turn on and off at random. Pulled into the lot where you line up with horns blaring. Before the parade I just tore a bunch of wires off a junction block so it wouldn't go off since both horns were behind the grill and in front of the radiator where i couldn't get to them.

Sorry I don't have a solution for you but I had to share my random horn story.

[magwakeenercew2jh]

Been dealing with this off and on all day. I think I'll take both Daner's and Yooper's tips a little further and take the steering wheel off, since it's been a few hours.... and it's still grounded.

What the heck, I was looking for something to do, anyway.

[magwakeenercew2jh]

Yooper,

For the record, I think our issue was the same. After I took off the wheel (again), I did a few things. Thanks to you, the first was to crank down a
little on the three cam housing "screws".

Then, I ground down a touch of the turn signal stalk....down by the flat part where the one screw holds it into the plastic turn signal cam housing.

After that, and while I was in there, I inspected my grounds ...or, actually, the buffer between the horn ring and the rest of anything else that could ground it.
I have a little resto-mod set up on the horn ring that was a little too close for comfort. So, I spaced it out from the wheel with some non-conductive material.

Good to go. Over a day has passed and no issues...hahahaha!!! Who knows?

Thanks again for the tips, you all.

[slikside]

Glad to hear that you have apparently solved your problem. Electrical problems can take some diggin!!!

I will add that my problem too, had to do with the turn signal lever, but it was because the lone screw by which it is attached to the cam had stripped out the hole in the cam. The lever was flopping around in there, making contact at random, causing the horn to sound same.

I pulled the steering wheel and replaced the screw with a slightly larger screw with more of a sheet metal vs. machine screw threading. the larger screw tightened up nicely onto the cam.....haven't had an errant horn since.

BTW, took the family to Yosemite last month, drove through your little town.......beautiful country.