Page 1 of 1

Faulty Horn

Posted: Tue Sep 09, 2014 3:36 pm
by bethfewster
Hello,

I have been recently putting my latest mog back on the road after 20 odd years, and one of the biggest issues im having is with the horn. Especially because me and electrics do not go so well together. It instantly confuses me. :(

I think I have established that the wiring is at fault, seeing as i've just gone and bought a new horn as the old one had stopped working. Only, I got the horn to work the other day after a lot of hassle, and going back to it today ready for the retest tomorrow, it has stopped working again.

I checked voltage at the horn, and from the brown/black wire, when the horn is pressed there is battery voltage. Yay. With the all brown wire, there is nothing, but I havent the foggiest whether this should be happening or if there should be battery voltage at both...Im debating rewiring the entire thing so I know it's all new and should be working, but I wouldnt know where to start with that either... :-?

If someone could point me in the right direction I would greatly appreciate it. :)

Re: Faulty Horn

Posted: Tue Sep 09, 2014 3:50 pm
by bmcecosse
The horn button works by earthing the return wire from the horn - therefore there should ALWAYS be 12 volts on both terminals of the horn - until you press the button - when one side (lilac/black) will drop to zero. Test the horn with a bit of wire - shorting the lilac/black side to a good earth. The lilac wire is fed from the non-ignition fuse - worth checking the fuse if no 12 volts and cleaning the contacts.

Re: Faulty Horn

Posted: Tue Sep 09, 2014 4:10 pm
by bethfewster
I only have a brown wire and a brown and black wire to the horn. But i know the horn definitely works, we tested it on my dads camper :) im afraid you're talking to quite the thicko when it comes to electrics, which is the non ignition fuse? :o

Re: Faulty Horn

Posted: Tue Sep 09, 2014 4:42 pm
by katy
Start the engine up, pull one fuse. If the engine stops you've found the ignition fuse, the other one will be the non-ignition fuse.
If you pull one fuse and the engine doesn't stop, you've found the non-ignition fuse. Simple like that.

Re: Faulty Horn

Posted: Tue Sep 09, 2014 5:02 pm
by POMMReg
katy wrote:Start the engine up, pull one fuse. If the engine stops you've found the ignition fuse, the other one will be the non-ignition fuse.
If you pull one fuse and the engine doesn't stop, you've found the non-ignition fuse. Simple like that.
Bit of a "Caveman" approach, but it works!

Ug ug

Re: Faulty Horn

Posted: Tue Sep 09, 2014 6:39 pm
by bmcecosse
NO - it won't! the Ignition circuit is NOT fused - so the engine will keep running with either or both fuses removed !! We should say 'Ignition controlled' - ie wipers/heater/brake lights/indicators - all these are powered from a fuse that is only live when the Ignition key is set ON. The other fuse (horn/interior light) is live all the time.. Your 'brown' is dirty Lilac....give it a wipe.... The non ignition fuse is the one with the LILAC wires attached.....

Re: Faulty Horn

Posted: Tue Sep 09, 2014 10:38 pm
by andy.pointeer
Hi the picture below shows the fuse box in my 66 Traveller (sorry its a bit fuzzy), should be the same in your 65. On the top left is the two lilac wires, one goes to the horn the other goes to the interior light.[frame]Image[/frame]

The next picture shows the horn, with one lilac wire from fuse and one lilac/black wire that goes to the horn button.[frame]Image[/frame]

Hope this helps.
You have not indicated if you have a fuse problem, but If the fuse keeps blowing, remove the lilac wires from fuse box one at a time to check if its the horn or the interior light. I had a problem with the interior light being wired incorrectly that kept blowing the fuse.

Re: Faulty Horn

Posted: Wed Sep 10, 2014 1:06 pm
by bethfewster
Thanks for all the help, it was the fuse, the metal prongs that held it in were incredibly loose, hence why it sometimes worked and sometimes didnt. I swapped it for an inline fuse and the horn works perfectly :)

Re: Faulty Horn

Posted: Wed Sep 10, 2014 3:58 pm
by bmcecosse
Well done -always carry a few spare fuses. But why did it blow ?? Or was it just poor contacts...?