Feed for horn

[chilly]

Sorry but I'm rubbish at electrics.
Can anyone suggest where I can get a feed for the horn that is only live when the ignition is on. I tried getting one from indicators but then they didn't work. Hence why I ask on here. The car has been converted to negative earth if that makes any difference. Ideally I'd like to just scotchlock or piggyback onto a suitable wire.
Thanks in anticipation
Chris

[Dean]

Sorry but I'm rubbish at electrics.
Can anyone suggest where I can get a feed for the horn that is only live when the ignition is on.

Does it work at the moment with the ignition off?

My first thoughts are, as the horn is an MOT requirement, you first need to be certain that if it is changed it is still legal.

Firstly the horn is on a cable that is part of a circuit. The cable goes from the fuse box and earths on the car body. On removing the wire you create a break in the circuit, which is possibly why other bits stop working.

The purple cable going to the horn, from the regulator is also part of the interior light circuit (if it is fitted). I think you need to take the purple cable out of the regulator and connect it to your ignition barrel. But in doing this you may be starving the interior light of it's earth. So you need to take another cable from the same connection on the regulator and connect it to the body. You will also have to fit a fuse to the circuit between the ignition and the horn.

Too be honest, it seems a whole load of hassle. I'd keep as it is.

That's if I have it right!!

[chilly]

Sorry, should have explained why. A week or so ago the horn started sounding on its own. I think I've sorted the short but I'm scared to death it does it again while we're away from the house. I've taken to disconnecting the horn to be on the safe side (which isn't ideal, obviously). I thought the obvious thing to do was to have it live only when ignition on.

[bmcecosse]

Change the feed from purple wire to green wire. Easily done at the fusebox - pull the purple off and plug it in beside the green wires on the other fuse! This may mean the interior light also only works when Ign ON - saves the battery running down accidentally! I've never understood why the horn is fed from a continuous supply - since it is not legal to sound it when the vehicle is not moving!

[chilly]

Thanks all

[mike.perry]

The feed to the horn is permanently live, purple wire, and it earths through the horn push, purple/black wire. Pos or neg earth will not make any difference. If the horn is sounding then there is a fault with the horn push or the purpe/black wire is shorting to earth. Unless you correct it the fault will still be there whether you run the horn from the live or ignition circuit.

[chilly]

The feed to the horn is permanently live, purple wire, and it earths through the horn push, purple/black wire. Pos or neg earth will not make any difference. If the horn is sounding then there is a fault with the horn push or the purpe/black wire is shorting to earth. Unless you correct it the fault will still be there whether you run the horn from the live or ignition circuit.

Very true Mike but at least it won't go off whilst sat on the drive and us not around. Like I say, I think I've found the short but, just in case I haven't cured it, don't want to risk it going off unattended.

[mike.perry]

Have faith, If you have found the problem and the horn does not sound whilst you are in the car then it will not sound when you are not there - unless it gets lonely when left on its own.