Horn button wiring.

[MNlotus]

I recently ordered the horn button along with my removable steering wheel. My old steering wheel had the ring contact type of horn pictured here…

http://caterhamparts.co.uk/product.php?id_product=1310

This had only one wire for the horn. I took a picture of the wire under the dash that it led to, it was the purple wire with the white plastic end that has scotch tape on it. Do i need any other wires for the horn button to work? there are 4 terminals on the back of the horn button.

[WestTexasS2K]

The horn button just completes a circuit. Most massed produced cars will run 12v thru the horn button but they don't have removable steering wheels.

I would think running a ground thru it might be a better way so that it doesn't accidentally get shorted out if something metal hits it like a seat belt latch or some other odd occurance. Horn would just honk instead of blowing a fuse. My 2 I'm sure others will chime in.

[xcarguy]

I second your 2 with my 2; that's 4 cents worth, sir.

[escondidoron]

The horn button just completes a circuit. Most massed produced cars will run 12v thru the horn button but they don't have removable steering wheels.

I would think running a ground thru it might be a better way so that it doesn't accidentally get shorted out if something metal hits it like a seat belt latch or some other odd occurance. Horn would just honk instead of blowing a fuse. My 2 I'm sure others will chime in.

 

Correct, the horn button is simply a make or break switch.

 

 

Most massed produced cars will run 12v thru the horn button but they don't have removable steering wheels.

I would think running a ground thru it might be a better way so that it doesn't accidentally get shorted out if something metal hits it like a seat belt latch or some other odd occurance.

 

I think that you've got this pretty close. In my experience, most cars run a ground wire to the horn button for exactly the reasons you have listed.

 

FYI, for similar reasons, the door switches for the dome light(s) in most cars also use the ground connection to operate the overhead lamp(s).

[NVP66S]

In most cars, the horn button grounds the single wire, which grounds the relay coil. Therefore the other end of the coil needs to be hot 12V. Similarly, one of the relay contacts needs to be driven by 12V, with the other going to the horn(s), as the horn itself usually has one side grounded.

 

Caterhams may be different though.....

[s2k7]

Overtime as you rack the steering wheel, the hot (12v) wire breaks and touch the metal.

Put a fuse on the hot wire....just to be safe.