My never ending battle with horns

[phish1270]

Tonight I start looking at where the 2 horns are mounted. They are both on the passenger's side of the radiator mounted to the core support. I decided to flip the brackets & change the way the horns were mounted so that I could make room for a nice, slim overflow bottle. I took the top horn off, flipped it on the mount & mounted it back on the car. It looked perfect with plenty of room for an overflow. I go over & hit the horn button, get a quick blurt from the horn & than nothing, just a clicking noise. Now the horns no longer work!:banghead:
I need some help figuring out what happened. Here is what I know & have tried:
The horn relay on the firewall clicks when I push the horn button. Working?
There are 3 wires plugged into it, a black on the bottom, purple in the middle & green on top. Purple & green share a 2 slot plug, black is by itself.
I have power at the purple wire always, I get power at the green wire when I press the horn button.
I have the same green wire plugged into the top horn & a piggy back wire running to the lower horn. I have power at the top horn when I press the horn button & also at the lower horn.
I have good continuity through the green wire from the relay to top horn & from there to the lower horn.
I sanded down all connecting points on the back of the top horn, its bracket & the core support to get a good ground.
I have not touched the lower horn at all yet but it is getting power & did work before.
Am I missing something? If the relay is clicking does that mean it is good? Do horns go bad? Seriously, all I did was flip the horn on the bracket & now it does not work! :angryfir: Please help if you have any suggestions, other things I should test or any questions.Any help is greatly appreciated!

 

[67Dart273]

Horns go bad or get out of adjustment. Are you sure they are grounded? Yeah, I know, I know, you MOUNTED them, here's a true story:

About 20 years ago, customer came in with landing lights (4537's, look 'em up) mounted in cans on his front bumper---bumper is bolted DIRECTLY TO THE FRAME of his old Ford pu. Lights don't work. I take a meter from battery NEG to the bumper and the BUMPER is not grounded!!! It's so rusty it's not grounding to the frame!!!

So pull at least one horn off, use a large wire and jumper the horn DIRECTLY across the battery until you are satisfied IT WORKS. Fiddle with the adjuster if necessary. Be careful when doing this you can get YES!! SHOCKED!! due to "inductive kick" from the horn

Then remount, be sure it's grounded.


You can also check the ground:

RECHECK power on the green with horn button down, I.E. power to horns.

Now put your probe DIRECTLY on the horn case, the other probe still on ground, see if you read any power

 

[phish1270]

So if I ground the bracket to the negative post on the battery & run power to the horn it should "honk"? Is the relay working if it is clicking? I definitely have power at both horns when I press the horn button. I have 2 spare horns removed from a Dart, I am going to try those also.

 

[RedFish]

The 12 v positive is always there. The horn button simply supplies ground signal to close the relay. The horns must be chassis grounded. Moving them to painted sheet metal may have interupted that ground path. If you know that ground is good,
You can take the 12 V from the relay directly to the horn or supply the ground signal to the relay. Bang on the horn body with a screwdriver handle or similar. Wake up the neighborhood by exercising the crap out of those horns. Yeah they stick. Like the old saying "If you don't use it you'll loose it". LOL
Hope this helps.

 

[phish1270]

The 12 v positive is always there. The horn button simply supplies ground signal to close the relay. The horns must be chassis grounded. Moving them to painted sheet metal may have interupted that ground path. If you know that ground is good,
You can take the 12 V from the relay directly to the horn or supply the ground signal to the relay. Bang on the horn body with a screwdriver handle or similar. Wake up the neighborhood by exercising the crap out of those horns. Yeah they stick. Like the old saying "If you don't use it you'll loose it". LOL
Hope this helps.

Red - All I did was flip the mounting bracket & bolted it back through the same hole. I ground the paint off of every contacting surface, I scared the boys with all the sparks. I also pounded on the horn with the heavy end of my ratchet thinking it might be stuck. I use them regularly, I am a Northerner living in the South! They worked before I flipped the bracket. When I plugged the horn back in after flipping the bracket it worked for a quick "honk" & then stopped. I will continue to mess with them until I get them working again but this is aggravating. Thanks for the help.

 

[DRENO]

Just a guess but if you put them back the way they were and they work it probably is the horn. A friend gave me a box of horns,some didn't work,I gave them to my Dad and he fixed a couple so I'm thinking they can be fixed,probably not worth the effort tho. Just my .02 8)

 

[805moparkid]

becarfull... i had the same kinda of thing happen... was driving one nite and all of a sudden both horns go off for no reason! then go off

about a week later i finish working on the dart close the hood...

somebody said ur cars smoking...

i turned around and the car was engulfed in smoke, ripped the hood open and yanked the battery cable off...

half my wiring sheerness was burnt up, from the horn all the way up into the dash... one of them must have shorted out or something

just be careful...

 

[phish1270]

becarfull... i had the same kinda of thing happen... was driving one nite and all of a sudden both horns go off for no reason! then go off

about a week later i finish working on the dart close the hood...

somebody said ur cars smoking...

i turned around and the car was engulfed in smoke, ripped the hood open and yanked the battery cable off...

half my wiring sheerness was burnt up, from the horn all the way up into the dash... one of them must have shorted out or something

just be careful...

That is exactly what I am worried about! I left the horn unplugged last night until I can figure out what is going on. I am just looking for the correct way to test the horn, how to know if the relay is working right & what is involved int he whole circuit. I can't believe the trouble flipping the bracket has caused. Thanks

 

[67Dart273]

So if I ground the bracket to the negative post on the battery & run power to the horn it should "honk"? .

Yes, this just confirms that the horn hasn't suddenly decided to quit, and at least some of them should have an adjuster screw

Is the relay working if it is clicking? I definitely have power at both horns when I press the horn button..

The key word is "power at the horns"

The relay can click but have bad contacts. Because you say you checked power at the horns, then the contacts should be good.

Seems weird that BOTH of two horns would quit. You are missing something really simple---they aren't complicated It's why I suggested you directly test the horns.

CAREFULLY recheck power to the horns---you getting close to battery voltage, or just "some power?"

 

[phish1270]

CAREFULLY recheck power to the horns---you getting close to battery voltage, or just "some power?"

I was just using a test light. When we pushed the horn button the light lit up. I did not check for voltage. I guess I need to use my other tester & test what voltage I am getting at the horns. I am also going to test each horn with a hot wire to be sure they work. I am sure I am missing something other than the common sense to leave things alone. If I can't move a horn bracket without breaking something than I have no right to own a 45 year old car!:-D

Thanks

 

[phish1270]

Alright, well last night I took both original horns off the car. Tested them along with 2 spares I took off of a '72 Dart I stripped. It is always good to save as many things as possible; you never know when they may come in handy although my wife does not fully understand that. The horns from the Barracuda would not work; the lower one looks like it has not worked in years, it had a hornets nest in it! The horns from the Dart work great & are smaller. I mounted one at the top location, wired it up & it works! :cheers: It is plenty loud enough so is there any harm in going with just the one horn? It leaves me enough room to add an overflow & sounds fine. Now I just need to clean up some wiring & move on. Thanks for all the help guys! If I can ever help....

 

[RedFish]

The high/low pair is not so much about loudness but tone. The pair produce a cord like sound. A single high horn is a harsh note but fine.
Happy moparing