horn troubles

for some odd reason my horn wont work, any suggestions on how to test/fix it?

Make sure that it is getting power first, use a meter or test bulb or something, so you know that your problem is the horn itself. There is a little adjustment screw on the face of the horn, you could try and fiddle with that. On my old 750, the horn sounded like a sick sheep til I adjusted that screw, with some diddling it sounds pretty strong now. Or, your horn could be junk. They come up on eBay pretty regularly.

Remove the horn. Get two wires and connect them to the two lugs on the horn. Put one wire on your hot battery terminal and the other on your ground. Does it blow?

If no, then try adjusting the small flat head screw on the back. If it still doens't blow, replace the horn.
If yes, then put the horn back where it came from.

Next, if your horn blew, chase the black wire and make sure it is securely connected. This is the ground. The hot wire is brown. It comes from your horn button. When the button is pushed, power goes through the button to the horn. This means that the button ALWAYS has switched hot power on the back side of the button. Take a multimeter and turn on your key and see if you have voltage there (you will have to open up your left switchgear). If you have no power, the brown wire isn't connected to your wiring harness which has a number of brown wires that will be powered, trace the wire back to the harness and fix the break. If the wire IS powered, check the other side of the button for power.

OK, the brown wire that hooks to the horn... connect your multimeter POS lead and put the NEG lead on a frame ground. Put the meter in VDC scale and turn the key on. Then push the horn button. If you have power, the horn will work (unless ground is bad since you tested horn) and if you don't have power, the horn button is the problem. Clean the contacts with an emory board or steel wool or replace.

Yeah, what he said. I knew somebody like WG could give you complete instructions on how to track down your problem.

If you ride in Boston, you might want to consider getting a big ol' airhorn!

alright i have an update. i took WG's advice and used two different extra wires and tested the horn on the positive battery terminal and a ground and it works. then i used the new ground with the old existing power wire on the bike and it blew the horn. then i used the old ground with the new power wire connected the battery and it didnt blow. now the two horn wires go into a large bundle of wires that looks like its wrapped up together with many different wires. any ideas on what i need to do now?

WG could probably answer this better, but it sounds like you have isolated the problem to a bad ground wire to the horn. You could open up enough of the wiring harness to track back to where the horn ground joins other ground wires. If everything else on the bike works (therefore is grounded properly) then your problem is in that short length of wire, and you should be able to replace it fairly easily. Or... you could run a new ground wire from the horn to any suitable ground on the bike... I would try replacing the wire first, try to keep the wiring as close as possible to original... Just my 2 cents worth.

just an addition, wen i had hooked up the old positive with the new ground to a chassis ground, the horn went off without me hitting the horn button at all. idk what this could mean

usually power goes directly to the horn.

the handle bar switch controls the ground.

having the switch on the negative side of the circut prevents arking arching ??

alright thats a relief then, so its definately the ground , but i really dont wanna just start opening up all those wires bunched together. any advice?

Does your Neutral indicator light work? It is fed by the same wire that feeds the horn (brown) according to the wiring diagram, and it also supplies the brake light circuit.

Post edited by: steell, at: 2006/07/17 01:11

yup, my neutral light works fine, as does every other eletrical component, thats y i really dont wanna dig into that line unless i have to

time to clean the contacts inside the left switch housing or have you done that yet?

the horn momentary switch contacts and spring disassemble with a #1 and #2 phillips driver.
fine sandpaper to shine up the brass.
reassemble with dielectric grease it will prevent oxidation but it is not serious if you don't have any.