Not to toot my own horn but........

[jamman18]

Hi,

I recently bought a new horn for my 77 as the old one wore out.  The button did not work either so I just decided to start from scratch and got new wiring and a new button.  Hooked up power from positive terminal of battery to button and then from the other side of the button to one side of the horn. The other side of horn I ran a wire to ground on the frame under the tank.  Horn works, just intermittently. No rhyme or reason as to when it works.  I checked continuity and power to all lines and I am good. I thought maybe where I have the wire from the horn grounded I should scrape off the paint to get a better connection. Other than that, I thought maybe a defective switch?  Any other thoughts?

Thanks!

[sgtslag]

1) Put a 5 Amp fuse inline between the battery and the button of the horn circuit!!!  (Without a fuse, a short could cause a fire, or worse...)

2) Check your connectors:  if you used crimped wire connectors, try soldering them, as crimps can fail, easily.  

3) Check your ground connection, to make sure it has continuity to the negative terminal on the battery -- use a digital volt/ohm meter, and wiggle the wires while you have the leads connected to look for loose connections.

4) Apply electrical contact grease to the connectors, and terminals, to avoid oxidation.

Best of luck!  Cheers!

[jamman18]

Great!  Thanks!

[TOOLS1]

To properly hook up a horn, you run a hot wire to the horn. Then run the ground wire from the horn to the button. This way the button is grounding the horn.
TOOLS

[jamman18]

So I don't need the fuse or still put it in?  And would I keep the same hot side of the button to go to the one side of the horn and then the other side of the horn to go back to the ground of the side of the button that has no wire? (positive term of batt to one side of button, same side to one of the horn connections and the another wire from opposite side of the horn back to the side of the button with no connection?)  

I noticed that if I don't separate the hot wire to one side of the button and then from the other side of the butoon to the horn, the button does not let the current flow through when pressed.

Hope that makes sense.

[TOOLS1]

I'll try this again. Positive to fuse, Fuse to horn, horn to button. When the button is pushed, it grounds the circuit through the button housing, and completes the circuit.
TOOLS

[jamman18]

Thanks! I'll give that a shot!

[Lucky 1]

The reason your horn does not work properly is that you put the ground to the frame under the tank
and the switch is on the handlebars. The connection is weak because your horn is trying to ground through the steering head bearings and any powder coat on the handlebars.

The ground from the horn should go to the green ground wire from the main harness.

[jamman18]

Ok, but tools said that I need to ground to the button instead of the frame....or are they both viable options?

[sgtslag]

From a physics/electrical standpoint, it won't matter if the switch is on the ground side, or the power side, as electricity requires a complete circuit/circle, to flow.  It will work, either way.  Cheers!

[jamman18]

Cool!  Thanks!

[jamman18]

Well, I got things wired ok only to find out that I have a defective horn!  Hooked it up directly to a battery and nothing!  

[Lucky 1]

Try tapping on the horn when it has voltage on it.
Sometimes they get stuck from sitting.

[jamman18]

The 5 amp kept blowing......how about a 15 amp?

[jamman18]

What should I be tapping on the horn with?.....and how hard?

[Hellbilly429]

tap it with anything really, just need to get it to vibrate to make the noise, but if you hook it up and tap it and it doesnt make any noise then it's prob shot.

[TOOLS1]

Horns draw a lot of amps. That's why the switch is in the ground. It would burn up on the hot side.
TOOLS

[pat english]

ill sell ya a horn for $5 bucks..dont know if it works tho..

[shinyribs]

LOL! Salesman of the Year Award goes to....sorry bud. Laughing so hard right now...

[pat english]

lol..yep thats me