[427L88]

OK so one of the first things I notice "post storage" is the horns dont work. I replaced the steering wheel chrome and thought I did a good job of the internal connections, including cleaning them. Horn buttons to firewall connection check out OK. Firewall to horn relay checks out OK ( the little black ground wire ).

Horns will run with a straight 12v from bat.

Bought a new horn relay from GU ( fancy cad plated one! ).

OK now it at least buzzes the relay, but still no horns.

There must be some anomoly somewhere, sicne all of the individual pieces check out ok.

Man, all I did is paint the stinkin' horns! ( in place!).

Any thoughts???? THNX!

 

[John_Muha]

Does the horns work or the relay click if you:
Ground the wire that goes up to the horn button. Find a good ground under the hood. Grounding that lead or relay terminal should close the horn relay.

 

[427L88]

I'll try it John. THNX.

 

[John_Muha]

May end up to be the rag joint. Since you checked and changed a few things just guessing that the rag joint coupling may have oxidized slightly because the car had sat. The horn button gets its ground from the steering shaft, not the column housing. The steering shaft is grounded through the rag joint to the gear box. If it is the rag joint, a small ground strap across it should do the job.

 

[427L88]

THNX John, I didnt know that. I was thinking somehow painting of the horns screwed up the ground, but you know what, that steering shaft has a nice fresh coating of "cast natural" paint as well.

Just jump from one side to the other with a copper strap?
You mean I didnt need that new $25 relay!?

 

[John_Muha]

"I was thinking somehow painting of the horns screwed up the ground"

Not if they are screwed in place, you give them 12 volts, and they go honk. They won't do that without a good ground.

"but you know what, that steering shaft has a nice fresh coating of "cast natural" paint as well."

The paint on the outside isn't the problem as much as the rag joint connection.

"Just jump from one side to the other with a copper strap?"

That will do it if that's the problem. If everything else is OK, (sounds like it is) you can just try grounding the upper steering shaft. If you take a battery jumper cable, bite one end on the upper steering shaft somewhere, attach the other end to battery (-), then try pressing the horn button. This grounds the upper shaft and will prove the rag joint is the problem. The jumper across the rag joint is the cheap easy way to fix it.

"You mean I didnt need that new $25 relay!?"

Can't answer that. You can test the old relay if you want to. Perhaps just an effort to stimulate retail sales.

 

[427L88]

Aw well Ground UP is sponsoring our show, and the new one IS PRETTY!

THNX a bunch John. Now I know what to look at. Confused by such a simple system! Doh!

 

[427L88]

Ok still confuaed. made a "jumper" and the relay buzzes when you ground it to the steering box ( or wherever), but the horns don;t sound.

It must be the ground on the horns??

 

[JimN]

There is an adjustment screw on the horn. You might try turning it just a bit to see if the horn will sound.

 

[cjlandry]

Since you said that it showed up after the car was sitting, I'm thinking there's a little corrosion between the horn mount and the core support that's causing grounding trouble.

Not at all difficult to check if you haven't already. Little things like this can drive you batty!

As an electrician whose primary job is troubleshooting and repairs, I find that 98% of the time the trouble is something very simple.

And with old cars, 99% of the time it's a grounding issue.

 

[427L88]

Turned the "adjustment screw" counterclockwise a bit, unmounted and sanded the mating surfaces on the horns, and still " buzzz" but no beep beep. This is getting interesting. I'm going to make another jumper so I can see if 12V flows out of the relay when actuated. Doesnt seem so.

Could the new relay from G.U. be faulty???

Remember, its me, ANYTHING is possible!

How to test the relay??

 

[cjlandry]

I just re-read your original post. Since you're saying that the horn sounds with a direct 12V jumped from the battery, I think you do have a faulty relay.

Check to be sure you have good voltage and ground going into the relay's coil.

Just because it puts out 12V doesn't mean it's carrying enough current to sound the horn. Could be a bad contactor inside the relay.

 

[427L88]

I have the same voltage at the relay that I have at the battery, ground is good. so.....I hope they accept a return , I think I've eliminated all other variables.

LAST thing I'll check is to provide a direct ground off the back of the relay itself and see if possibly its not grounding against the core support as it should.

Damn, it took me less time to degree in a camshaft!

 

[Chevello]

Is the relay clicking and the horn buzzing? or is it the relay buzzing?

If its the realy buzzing, then there has to be an insufficient voltage prob at the relay coil circuit. If its the horn, then it would be the same problem, but in the relay contact side.

If you can trigger the relay and sound the horn with jumper wires, then it has to be up in the column someplace. Have you tried to jump the contacts under the horn button yet?

K

 

[427L88]

DOH! You knew it was going to be a DOH! The new relay has an additional contact away from the terminals on the left . Anyway, a glance at the old relay clued me that i hadnt hooked it up right.

Now only thing buzzing is my head!

Well, at least I know my forward wiring harness is ok.

 

[pmullaly]

Now reset your "adjustment screw" that screw is used to adjust the AMP draw of the horn thus altering its tone.
Do a search for it using my member # I posted the info quite awhile back

 

[SS70SS]

The relay needs a good ground also for it's coil
the work correctly.