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Misbehaving horn

9-11-09 (M/D/Yr)

After setting quietly from 4 to 6 hours in my driveway the horn of my 1999 Buick LeSabre (48,400 miles) starts to soundoff continuously until I disconnect the negative terminal from the battery (I get no pleasure from doing that, the first time was 2:30 AM, second time at 4:30 AM different mornings). The above has occured twice. First time was after a rain, second time there was fog in the area, and both times the temp was approximately 62 degrees F. Gee, do ya think it could be moisture? I’ve talked to the local Buick dealer’s service department to no avail. Any suggestions beside disconnecting the horn? Which I will do when I find it.

Please advise. HerbandRay.

PS: Can you help me with the code to restart the radio? hrclaw@mtco.com

Three things can cause this.

The horn contacts in the steering wheel, the clock spring behind the steering wheel, or the horn relay.

If it were me? I’d pull the horn fuse, and instead of the horn, I’d just roll the window down, stick my head out and yell, “Get the hell out of my way!”

Tester

I had the same problem with a 1971 Ford Maverick Grabber that I once owned and my brother had this problem with a 1977 Cadillac DeVille. In both cases it turned out to be the the contacts in the horn switch on the steering wheel. On these cars it was an easy do-it-yourself repair. However, with the airbag in the steering wheel as it is on most cars, this may not be an inexpensive do-it-yourself repair.

However, there is a cheap way out. Most horns have a relay that when the horn button is pressed, the circuit through a small electromagnet in the relay is completed to ground, and the electormagnet pulls the contacts together that power the horn. You could bypass the wiring to the horn switch in the steering wheel by purchasing a horn button kit. These are available from J.C. Whitney and probably many auto parts stores. This button mounts on the side of the steering column. It won’t look original, but is an inexpensive way to make the repair. I “repaired” the horn on my 1950 Chevrolet pick-up truck this way–worked just fine.

To Tester: Novel solution, but doesn’t solve the problem. Thanks anyway. HerbandRay.

Are you going to sleep through the night? I would call that problem solved. Especially on a ten year old GM vehicle.

Tester

Tester: You bet I will. HerbandRay.

I beg to differ. Pulling the fuse will, indeed, solve the problem of the horn going off in the middle of the night. The horn will not sound, for any reason, if you pull the fuse.

I can’t remember ONE time in the last twenty years that I’ve used the horn on any of my vehicles, for any reason. I’d pull the fuse. Any other fix will cost money. Pulling the fuse costs nothing.

If you insist on fixing the horn, I’d follow Tester’s advice. He’s always right. I’d test the horn relay first.

Radio Code? Good luck. The dealer will probably charge for it.

Doesn’t that seem wrong? It’s YOUR radio. Why should you have to pay to make it work again after you disconnected the battery?

I agree, thanks for your iinput. HerbandRay.

One other idea: Pull the fuse on the horn and install a “Wolf Whistle” horn that is powered by engine vacuum. I haven’t seen or heard one of these for years, but if they are still available, I might get one so that I can toot at the babes as I cruise the nursing homes.

Triedag:
Looked for, but no fuse just for horn, so disconncted horn and will think of something else to replace. Maybe an air powered Diesel train horn, that ought to get some attention. Thanks to all for your suggestions, good by all. H&R