RedZR

All,

I have been searching the archives for some help with a horn problem I am having on a 1978 Pace Car.

Basically, the horns blow all the time. Thus far I have done the follwing (with the displayed results):

1) disconnected the little "harmonica" fitting on the column to see if they would shut off- which would indicate a horn button problem. They did not stop.

2) I plugged that back in and then removed the horn relay/door buzzer and they still blow.

Anyone have any ideas?

Also, does anyone have a wiring diagram of the horn system for a 78 they could share?

Thanks,
Dan

taylorbg

Mine will do that every once in a while on my 77. Inside the horn is a bar that when pushed touches metal and then sounds the alarm. It has probably come loose and is always touching the metal.

...Roger...

You might not have pulled the horn relay. The buzzer is not the relay. The relay is usually over the fuse box and maybe a little to the outside of the car.

...Roger...

http://www.corvetteforum.net/c3/tune.../index20.shtml

Gerry80

It sounds like either someone bubba'd it and accidentially made the horns hot, or the horn wire is loose and has come into contact somehow with a hot wire. Without the horn relay there's no way the horns should be getting any power. You might have to trace those wires.

I don't know if your 78 is similar to my 80, but the horn is fed off the courtesy/clock fuse (hot at all times), orange wire feeds to relay. Black wire out of relay to horn switch which when depresses, grounds the relay and closes the contacts which carry the power from the orange wire to the green wire to the horns. There's a wiring connector at the firewall that may be where your horns are getting hot (sounds kinda kinky

Gerry80

Roger, I guess I can't type fast enough.

RedZR

Ok- new developments- thanks to Roger. I mis understood where the relay was and went back to the garage and fund the relay. I unhooked it and now the horns do not work

I removed the little cover from the relay and the two contact points were apart from each other, however I found that if I simply touched them together they would stick. It looks as if it may have been hot inside the relay at one point that the contact points almost welded themseves together. I took a fine piece of sandpaper and cleand them and reinstalled the relay and the horns still do not work. I may have messed the relay up when I was sanding it and have the contacts too far apart. So, tomorrow I am going to pick up a relay to see if that does the trick.

Does this sound reasonable? I assume Advance Auto Parts has these things, correct?

Thanks to everyone for answering my questions so promptly!

Dan

...Roger...

Sounds like you got it. Make sure while messing with the relay you didn't blow the STOP fuse.
http://shop.advanceautoparts.com/web...S_784896136___

RedZR

Ok- I found the problem. I replaced the relay and still no workie .....then I removed the horn button along with the three screws that retain the part that hold the horn button on and found the problem.

There is a shaft that should house a spring loaded tab that grounds to the lower part of the horn contact when the button is pushed and that little piece is missing. Does anyone know the part number for that thing?

Soooooo close !!!!!! I grounded the tow contacts and the horn works fine. I just need that little piece and will be finished !

Dan

...Roger...

Unplugging the harmonica connector should have shut the horn off if the horn switch was the problem.

tonak

http://www.ecklers.com/product.asp?p...5&dept_id=1714

Maybe?

RedZR

All- I have all the parts to complete my horn assembly- I was missing the little pin and spring assembly that fits into the shaft in the wheel. I trimmed the shaft to 3/4 of an inch (per the instructions) and put everything back together.

Now, the horn blows all the time. The relay is brand new- so I know that is not the issue. Could someone post a picture of how this goes back together. Assuming I have everything reconnected properly- why shoudl the horn blow all the time?

Thank you!
Dan

RedZR

My car is now 100% operatuional as far as the electronics go. The trouble with the horn was that the little black spring that the born button attaches to did not have enough of an arch to it and was grounding against the other piece that it bumps against to make the horn sound. I simply re-bent it a little and now it works just fine!


When I got the car last week I noticed that someone had wrapped tin foil around one of the fuses and the horns did not work. With the help of this forum I removed all that stuuf and checked the wiring for problems and was lucky enough to not find any "bubba work" beyond that.

Now I simply change the rear calipers and I will be good to go!

Dan

...Roger...

Good luck

...Roger...

You might want to read this.
http://forums.corvetteforum.com/c3-t...fo-please.html