Fuse #6, hazard + horns circuit, blows

[opethmike]

The other day while driving, I used the horn, and it worked, but sounded strange/weak. Yes, even more so than normal.

And I noticed today that my horn wasn't working at all anymore. Naturally, first thing I checked was the fuse. It was blown. So I went to replace it, and as soon as I put the new fuse in, it blew right away. Didn't even have to operate either the horn or the hazards.

Not great with electrics, so help would be appreciated please.

[Ron]

The other day while driving, I used the horn, and it worked, but sounded strange/weak. Yes, even more so than normal.

And I noticed today that my horn wasn't working at all anymore. Naturally, first thing I checked was the fuse. It was blown. So I went to replace it, and as soon as I put the new fuse in, it blew right away. Didn't even have to operate either the horn or the hazards.

Not great with electrics, so help would be appreciated please.

#6 powers the buzzer box, hazard switch, and light switch. So you could unplug them one at a time to see if the fuse(s) stop blowing and go from there. But if either of the pink wires at the fuse has been spliced (or you don't mind a splice), you can gain a lot of info disconnecting either one...

[Kevin]

+1 to Ron, though I don't think the light switch is on the same circuit.

I am curious about the horn circuit since it sounded strange/weak. If all the items on the #6 circuit are wired in parallel, which they appear to be, shouldn't the horns be getting a full 12V if they're getting power at all?

Anyway, unplugging the buzzer and hazard switch should isolate things for us, assuming the short isn't in the wiring before those.

[Bitsyncmaster]

Horns should only draw power with the horn switch pressed. Maybe your horn switch broke.

[DMC5180]

+1 to Ron, though I don't think the light switch is on the same circuit.

I am curious about the horn circuit since it sounded strange/weak. If all the items on the #6 circuit are wired in parallel, which they appear to be, shouldn't the horns be getting a full 12V if they're getting power at all?

Anyway, unplugging the buzzer and hazard switch should isolate things for us, assuming the short isn't in the wiring before those.

30+year old horns are on a car that's been driven in the elements are junk. Replace with NOS or a generic HI/LO note set. Their CHEAP!

[Ron]

+1 to Ron, though I don't think the light switch is on the same circuit.
I should of been clearer...
Not the "Main Light Switch #70"...I meant the one connected to the horn, "Light/Signal/Horn #71".


I am curious about the horn circuit since it sounded strange/weak. If all the items on the #6 circuit are wired in parallel, which they appear to be, shouldn't the horns be getting a full 12V if they're getting power at all?
Suppose the leg feeding the horn was pinched and grounded, but not a good connection. Then when he presses the switch, the short is in series so it will rob "power" making the horn sound odd.
And, if he keeps trying it, the connection at the short could fuse making a better/solid connection and eventually overheat the switch causing it to fuse and always be On. (Note the fuse may not blow because it is for the wires, not the devices connected to them, and 20 Amps is a lot to run through a horn switch!)
But I'm with Dave and going with a failing switch so far.



Anyway, unplugging the buzzer and hazard switch should isolate things for us, assuming the short isn't in the wiring before those.
Looking at the Work Shop schematic:
Unplug "Buzzer" #246, "Hazard Switch #72", AND, "Light/Signal/Horn #71".

[Ron]

30+year old horns are on a car that's been driven in the elements are junk. Replace with NOS or a generic HI/LO note set. Their CHEAP!
I agree 100%, but he still has to figure out why the fuse blows w/o trying the horn...

[Kevin]

Suppose the leg feeding the horn was pinched and grounded, but not a good connection. Then when he presses the switch, the short is in series so it will rob "power" making the horn sound odd.
And, if he keeps trying it, the connection at the short could fuse making a better/solid connection and eventually overheat the switch causing it to fuse and always be On. (Note the fuse may not blow because it is for the wires, not the devices connected to them, and 20 Amps is a lot to run through a horn switch!)
But I'm with Dave and going with a failing switch so far.

Totally agree which I was curious about the horn circuit. I brought it up because I misread your post because of the light switch ambiguity, I thought you just wanted him to disconnect the buzzer and hazard switch. So, my bad, carry on!

[Ron]

Totally agree which I was curious about the horn circuit. I brought it up because I misread your post because of the light switch ambiguity, I thought you just wanted him to disconnect the buzzer and hazard switch. So, my bad, carry on!
No not at all...my bad! I'm glad you brought it up...I can see where he (or anyone) would interpret "Light Switch" to mean "Main Light Switch"...that's what I call it LOL!
The last thing I want to do is confuse him...THX!

=======

LMAO- I guess we're both bad:
You say above that you thought I "just wanted him to disconnect the buzzer and hazard switch."
But I said,

... the buzzer box, hazard switch, and light switch.

you said,

...unplugging the buzzer and hazard switch should isolate things for us.


Mike, you are on your own...:tongue:

[opethmike]

Just resolved this issue. I disconnected the horns, and put a new fuse in. It didn't immediately blow, like the fuses were doing last night. Saw right away that the horn connections were unbelievably dirty, but for shits and giggles, reconnected them. Fuse blew immediately.

So I cleaned the bejeebus out of the horn connections, hooked them back up, and installed a new fuse. Fuse didn't blow right away, nor did it blow while testing everything on that circuit. Horns even sound better than they have in years!

Thanks guys.

[Ron]

Mike,

You have an intermittent problem.
Like Bitsy said, the horns should only draw power with the horn switch pressed. The hot wire to the horn is not connected to anything otherwise, electrically, it's a dead end to nowhere.

Not to confuse things (again ;-), but corrosion can make the horn sound odd, but, again, it would have nothing to do with the fuse until you press the button.

[opethmike]

Hmmm, interesting. I'll keep an eye on it.