horn works sometimes, sometimes doesn't

[DeuceNewb]

My horn has started acting funny lately. When i hit the button, sometimes it won't work. Keep driving and maybe later on it will work. Today, it didn't work at all, but last time i drove it worked fine, then went to honk it and nothing, and right before i shut her down at home, it worked again just fine. I don't understand what is making it work intermittently. maybe the switch or something?

 

[kendelrio]

Sounds like a wire in the steering wheel.

 

[Stretch44875]

Mine only works when the engine is running...switch for engine can be on, but still only works when the engine is running. Maybe a voltage problem for mine, yours sounds like bad connection, which is possible on the steering column wire.

 

[m16ty]

I had the same problem with my horn only working sometimes. Come to find out it was the juction block on the drivers side firewall that supplies power to the horn. The connector was loose and wasn't making connection all the time. I've run into this on several of the military pin type connectors. To fix I just take a pair of pliers and squeze the female to make a tighter fit on the pin.

First thing you need to find out is if you've got 24v to the horn. There is 24v at the horn any time the light switch is in stop light or service drive. If you've got 24v at the horn you can test to see if the horn itself is good by grounding the other pin on the horn to the frame. The horn should blow. If all that checks out then check the wire from the horn, through the sterring box, and up to the button.

 

[DeuceNewb]

awesome. that sounds good. I will check all that out tomorrow when the weather isn't so cold out anymore

 

[Lex_Ordo]

I recently changed my steering wheel and along with it, replaced the horn wire lead that connects to the rest of the harness in front of the steering gear box, and the horn button. I upgraded to the newer style.

Got the wire leads and the horn button kit from Saturn Surplus. It is an easy swap out. use a saftey wire to remove the old wire, then pull the new wire back through.
Cut and crimp a water proof connection to the wheel end of the wire(all part of the newer horn button kit, connect up the horn and reattach the wire lead to the harness. That should be all there is to do.

 

[maddawg308]

I second the steering wheel column wire. I had that problem with my first deuce, and it was a PITA to fix it (the wire was a little short, apparently someone had already tried to fix it).

If you can find it, try upgrading to the new design horn setup. I did on my new deuce, and it eliminated all those crappy brass-colored disks and pieces that the old horn setup had. Sealed system, much better.

 

[Tackettr]

Actually, there is a 24 v hot wire at the horn solenoid all the time regardless of any switch location. That is, if it is wired correctly and connections are good. Both leads are mark 25 if I remember correctly, you have to use a voltmeter to figure our which one is hot.

The horn button just completes the ground.

 

[salmon71]

I've had a problem when the weather gets cold, the horn wouldn't work. I have a air horn in mine and it was the cold weather that would freeze the air line to the horn itself. I don't know if you have a air or 24V horn, but this is what I experienced. Hope this helps...

 

[m16ty]

Actually, there is a 24 v hot wire at the horn solenoid all the time regardless of any switch location. That is, if it is wired correctly and connections are good. Both leads are mark 25 if I remember correctly, you have to use a voltmeter to figure our which one is hot.

The horn button just completes the ground.

I haven't tried it but I was under the impression that the horn would not work if the 3-lever switch was off or on black-out lights. I know that's how my m715 is but I could be wrong on the deuce. Seems logical because you wouldn't want someone to hit the horn button durring BO conditions. When I was troubleshooting my horn the switch was in "stop light".

 

[Tackettr]

Not sure if BO modes disables horn circuit, but know for sure lead is hot in off position. Heater fan also runs since its tied into the same circuit. If horn doesn't work in BO mode then my heater doesn't either. I agree it makes since for it not to work in BO but I think it does.

 

[mhsnmk]

What Should You Do If Car Horn Is Working Sometimes And Sometimes Not?

Your car’s horn is a safety feature built into the car to help get others drivers attention if they start to get into your lane, or in other situations to warn people around you of your presence to prevent wrecks or injury.
This is why it is important for you to have a functioning horn. Sometimes though your horn may stop working. Normally there are a few possible problems if this happens. Continue reading to learn what these problems are and also solutions for them https://www.autoguysland.com/car-horn-not-working/

 

[rustystud]

Your car’s horn is a safety feature built into the car to help get others drivers attention if they start to get into your lane, or in other situations to warn people around you of your presence to prevent wrecks or injury.
This is why it is important for you to have a functioning horn. Sometimes though your horn may stop working. Normally there are a few possible problems if this happens. Continue reading to learn what these problems are and also solutions for them https://www.autoguysland.com/car-horn-not-working/

Considering our horns are electrical/air operated that article really doesn't apply to us.

 

[CMPPhil]

Old school for air horns rope to a mechanical valve.

 

[rustystud]

Old school for air horns rope to a mechanical valve.

There you go. Keep it simple.

 

[russojap]

Could somebody elaborate on how to change the horn to mechanical valve? I had mine working ( sort of ) before it sat for so long and now it won't do anything. I had installed a new button and solenoid before and it did work ,but never great, it was kind of weak most of the time. I never could figure out if it was a problem with air or electrical. If I recall correctly you could push the button and the horn might blow right then, or there could be a delay and then it would blow a little.

 

[CMPPhil]

Could somebody elaborate on how to change the horn to mechanical valve? ....

Hi
Bought what I believe are the horns for M35 that somebody had removed the electric valve, so just plumbed it in mounted it above the cab of the truck on the radio body box. Then plumbed in a 3/8 ball valve drilled hole in end of the handle hooked spring to handle to pull it closed, going the other way is a nylon cord up to the cab roof then forward to the windshield. To sound the horn just pull down the cord, pull a little and you get a polite toot, pull down hard you get real blast.

The truck is on is my CMP Pattern 13 3 ton radio truck, the truck doesn't have air brakes so the horns just run off an air tank. I mention this for two reasons no need for air brake certified fittings and the system is air tight enough that it will sit for months without loosing air.

I know it sounds crude, and it is, I put it on 10 years ago always planning to refine it if seemed to work well. It works so well that I never got around refining it.

Only problem I've had with it is wasp bulding a nest in one of the horns. After cleaning the horns wanted to test them, so stuffed a tennis ball in each horn expecting to mute the horns. It did, until there were two load pops and the tennis ball went flying across the shop.

Cheers Phil