Air horn fitting guide?

[P44YNE]

Anybody who might be able to help, I've been gifted an air horn and want to replace my standard horn with it (at least for a few weeks to show gratitude lol) but on attempt number one, got stuck because the two wires leading up to the standard horn weren't positive and negative as I'd anticipated but actually joined together inside the plug and are the sme colour.

I have a relay that requires a positive and negative from the horn, a battery feed, and a connection to the air horn which in turn needs to be earthed. I think!!!

Well that was the plan at least until the discovery of the two identical wires.

Is that right or where moght I have gone wrong?

Edited May 15, 2012 by P44YNE

[F3rAL]

I fitted one from ebay too, it says you need to have 30amp relay but it works fine on a factory 20a one.

wire that you have are both positive, negative comes from the mount. I would suggest you just to connect it to the stock wires with stock relay and don't hold a horn on for a long time and you will be fine, if you will, you will have to change a fuse

[P44YNE]

So basically the two stock wires to positive and make an earth for the negavive terminal on the air horn. No extra relay, no extra fuse in a new fuse holder?

Thanks for your help

[F3rAL]

Well depends what you have, my one was a simple 140db (i think) air horn, I thought I will try to connect it to the factory wiring if the fuse or relay goes I will change it but so far so good 10 months and everything is fine and I love to use it a lot I had to change fuse once, (it was a lot of traffic and ... )

If you have two wires connected together and everything works that must be a positive wire.

[metalmickey0]

You do know that to pass the mot you have to have a working elecrtic horn and a airhorn wont pass. thats what i`ve been told anyways.

[F3rAL]

Air horn will pass if it is a single tone horn, if it is a multitone horn it is illegal I was told