Dead Horns

First day out this season, I tried to honk my horn at a friend. Got nothin’.

I’ve spent that last couple days troubleshooting the system. I have voltage in the Dash Fuse Panel and there is voltage fed directly to the Sub Panel (with all 8 switches; 4 wipers, nav lights, deck lights, defrost fans and HORN). I tested each switch/breaker and had all voltage at every outgoing feed.

The horn wire goes up thru the stbd wall and into the shelf/cabinet above the helm then towards the forward centerline and disappears. I’m sure it goes thru the roof somewhere under that roof ridge cap. It has the horns, GPS antenna, TV antenna, mast with anchor light and spotlight plus the fake tug stack. I thought of dismounting the horns to do a bench test but the mounting bracket screws just spin. (Are they nutted under there?)

The horns themselves are connected with about two inches of wire. And those wires disappear into the horn housing. Even taking the horn partially apart, the wire connections are not accessible. With some long pieces of wire I was able to prove continuity of each wire, hot and ground.

So I’d have to say that the TWO horns are toast. Both at the same time???? Dunno. I guess I’ll have to buy a new set. If anyone has any ideas, now’s the time.

Even if I get new horns, I’ll have to hook them up. I’d rather not make splices in that short bit of slack wire coming out of that roof ridge cap. I would be especially unhappy if the new fans didn’t work and I’d be unable to return them with short lead wires.

I’m afraid my alternative is removing the cap. It looks like it’s held in place by 14 screws. Is it sealed/glued in place? What is the mounting arrangement for the mast? Again, if anyone has any comments, now’s the time.

Thanks for reading this far.

rich

viewtopic.php?f=7&t=2227
Most likely the contacts need to be cleaned. This link explains how to do it.

Thanks Brian !!!
That's gotta be a good next step.
I did get one horn partially apart. I didn't know that a screw was hidden under the nameplate.
I did see the points and thought they could be a problem. I checked and determined that they were not welded.

One other thing I didn't mention was that I saw no current flow when I tried the horn.

Stay tuned.

Still wondering what it's like under that cabin top.

rpmerrill":3lpdbxqq said:

Even if I get new horns, I’ll have to hook them up. I’d rather not make splices in that short bit of slack wire coming out of that roof ridge cap. I would be especially unhappy if the new fans didn’t work and I’d be unable to return them with short lead wires.

Click to expand...

Hey Rich,

If you did need to replace the horn I would cut the wires close to the old horn that no longer works so they way you have more length on the new set for install. Hope this helps.

Thanks,

rpmerrill":1v0a4jk0 said:

Even if I get new horns, I’ll have to hook them up. I’d rather not make splices in that short bit of slack wire coming out of that roof ridge cap. I would be especially unhappy if the new fans didn’t work and I’d be unable to return them with short lead wires.

Click to expand...

Hey Rich,

If you did need to replace the horn I would cut the wires close to the old horn that no longer works so they way you have more length on the new set for install. Hope this helps.

Thanks,

This is a very common problem. Moisture enters the horn and causes corrosion. The linked solution does solve it. Using dielectric grease on the contacts helps as well.

After you get them working again, I recommend getting into the habit of using them each time you leave your slip. They will stick if not used frequently.

Also see this recent thread on horns.
viewtopic.php?f=6&t=18004

More good stuff!

Thanks, all.
rich

Horns replaced. It wasn't too hard to do. But I was for sure careful with the couple inches of slack wire. Didn't want to screw up and have to do exploratory surgery removing the roof top cap.

The new horns, shown as an exact replacement on the West Marine site were NOT an exact replacement. They mounted a bit differently and the horn body screw locations (that needed to match the existing bracket) were off by about 3/23" - 1/8'. I mounted with one screw and a large washer on the second screw to secure them. (The forward trumpet clamps held everything nicely.)
Next time I get the chance I'll modify the bracket with my dremel. I don't expect that to go easy since it is stainless.

Follow up on the new horns installed last month.
I worked very hard to preserve every mm of wire leads when I connected the new horns to the boat.
The new horns worked.

Two weeks pass: Horns don't work. Tried multiple times in cool mornings and hot afternoons. Nothing, just a click.

Today I checked the voltage. The house voltage meter showed stuff happening when I hit the horn button. The house voltage would drop a couple tenths of a volt. I got my ammeter out and the horns were drawing a bit over 15 amps when the switch was hit. I tried plugging the horns into a different switch in the panel. Same effect.

I had a hard enough time believing that two OLD horns would both go bad at the same time.... let alone two NEW horns going bad at the same time.

What now?

rpmerrill":ygq8hy0k said:

...What now?

Click to expand...

How about a hand held horn in a cup holder near the helm? That was my solution.

Yup, I've had one of those since day one. It is just so un-tugly.

Actually I've never used either horn for anything other than "social" interaction.
And CG inspections.

Well, 15 amps seems like a large draw for horns. I would look at the literature or call the manufacturer to see if that draw is accurate with specs. If not, it sounds like a bad connection somewhere.