Air horns!!!!!!
Moderator: RichardW
Air horns!!!!!!
The horn on my xant is very very croaky,But I have a new set of air horns I have never used in the garage (about 6 years old) that still work when a 12v supply is put to them, Can I fit them straight on or is there any mods I will need to do to the wiring?
Is there a relay/fuse adequate for the horn already.
I'm a bit of a numpty when its comes to electrics so please talk slowly!![:D]
Is there a relay/fuse adequate for the horn already.
I'm a bit of a numpty when its comes to electrics so please talk slowly!![:D]
- fastandfurryous
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When you test the air horns, Use a multimeter on amps (big amps that is, at least 10) and see what it draws. Check your handbook, and see what the fuse that covers the horn circuit is, and what else it protects. As a very rough rule of thumb if the current drawn is less than half of the rating of the fuse, you should be fine.
If they draw big amps, then use the feed to the current horns to switch a relay. The relay will then draw straight from a +ve connection (like the battery) and that means you can use an inline fuse to protect the horn in isolation from everything else.
If they draw big amps, then use the feed to the current horns to switch a relay. The relay will then draw straight from a +ve connection (like the battery) and that means you can use an inline fuse to protect the horn in isolation from everything else.
The compressor for air horns usually pulls a bit more current than the standard horns. I have in the past wired air horns into the standard circuit with no ill effects - some will opperate from a relay already - though I will have to wait till I get home and check my BOL to see what the Xantias set up is.
Depending on the type of horn I would be tempted to fit an auxilairy relay with a fused feed from the battery just to be on the safe side. Maplin flog kits for lighting which could be employed to do the same thing.
Make sure your air horns are legal though or you will fall foul of Mr MOT inspector.
Depending on the type of horn I would be tempted to fit an auxilairy relay with a fused feed from the battery just to be on the safe side. Maplin flog kits for lighting which could be employed to do the same thing.
Make sure your air horns are legal though or you will fall foul of Mr MOT inspector.
I have them - a set of normal twintones, and a set that play dixie, as on the General Lee[:I]
Just use the wire to the standard tooter to trigger a relay run form the battery to operate the horns. You need a relay because of the rubbish ( BX, anyway..) wiring.
My Dixieland horns are run from a seperate switch-I don't want them going off by accident in the MOT.
Neither set uses any more current than a windscreen wiper motor would.
There is no substitute for a loud set of airhorns!![}:)][:)]
Just use the wire to the standard tooter to trigger a relay run form the battery to operate the horns. You need a relay because of the rubbish ( BX, anyway..) wiring.
My Dixieland horns are run from a seperate switch-I don't want them going off by accident in the MOT.
Neither set uses any more current than a windscreen wiper motor would.
There is no substitute for a loud set of airhorns!![}:)][:)]
As far as I can see the BX is wired without a relay as is ZX. Column switches are a nuisance if they burn out so I'd fit a relay with the operating side fed by the existing wiring and the horn itself fed by a convenient source. I am deliberately vague here as you will have to find a suitable source - for example starter solenoid or even the battery positive terminal but use a line fuse close to the source.
I think air horns are legal if they sound together - its when they sound in sequence that the problems come.
Jeremy
I think air horns are legal if they sound together - its when they sound in sequence that the problems come.
Jeremy
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Was forced to buy a set of air horns to MOT the Volcane, I only needed the trumpets but ended up getting the whole kit, there was a relay in the packet with them, IMHO the BX certainly needs five or six relays on assorted circuits, starter, lights etc I dont imagine the Xant is a lot different.[B)]
Stewart
Stewart
Paranoid, relays usually come with a connection diagram, so you shouldn't have too much trouble- they often have a little pictogram moulded into the case as well, If you are still stuck tomorrow I will go and have a look at whats on what terminal on mine.
You need a 4 terminal one- one terminal goes to the switch, one to earth. Another terminal goes to the battery and the fourth goes to the accsessory, and thence to earth. They have standard pin numbers but I can't remember which is which, but as I said above, you should get a little connection diagram with it.
When you press the switch, the light current operates a tiny solenoid in the relay, which switches the heavier current from the battery to the load.
Kowalski- yes they do run off a seperate switch- I have had them since about 1982 and they go from car to car, I'm a bit old for that sort of thing now, and the compressor is slowing down a bit too and could do with an overhaul but I just can't bring myself to get rid of them!!
I'm pretty sure they aren't legal, but I have never had any bother at MOT time because they don't run from the normal horn switch, and they are pretty obvious too- there are 5 horns and a compressor the size of a dustbin!!!!
You need a 4 terminal one- one terminal goes to the switch, one to earth. Another terminal goes to the battery and the fourth goes to the accsessory, and thence to earth. They have standard pin numbers but I can't remember which is which, but as I said above, you should get a little connection diagram with it.
When you press the switch, the light current operates a tiny solenoid in the relay, which switches the heavier current from the battery to the load.
Kowalski- yes they do run off a seperate switch- I have had them since about 1982 and they go from car to car, I'm a bit old for that sort of thing now, and the compressor is slowing down a bit too and could do with an overhaul but I just can't bring myself to get rid of them!!
I'm pretty sure they aren't legal, but I have never had any bother at MOT time because they don't run from the normal horn switch, and they are pretty obvious too- there are 5 horns and a compressor the size of a dustbin!!!!
oh yes they are illegal with out doubt, unless its for business but even then it has to have a standard horn and its not classed as a back up system in the event one goes down "in fact you could be done for it" and pressing the horn has a law unto its own and most dont observe the law including the police.