Topic: CB550 horn issues

[Mushman]

My ride is a 74 CB550K, mostly all original. Went to use the horn the other day and got nothing. So, pulled the horn itself, tested it on a spare battery and it worked fine. Now, keeping in mind I know zero about motorcycle electrics and don't even own a multimeter, I used a test light on the black power wire, key on , got juice. Plugged that wire back into the horn, connected the green wire coming from the horn to my test light and grounded it, expecting the horn to beep. It didn't, the test light lit up instead. So what's next? 


Brian

[bryanj]

Take the test light out and see if grounding the wire makes horn beep, if yes horn button not grounding properly

[BoneDigger]

You can also check the horn at the battery.  Power to positive and ground the other wire.  If no beep, it is the horn.  I have a 1972 CB750 which had a non-working horn.  Took it apart (pretty easy to do), cleaned up the components, and put it back together. There is a nut inside that regulates the horn vibration. I messed with different degrees of tightness  to get it to work properly. Last on is the cover.

[robvangulik]

So, pulled the horn itself, tested it on a spare battery and it worked fine.

Brian

Did you read the opening post?
I'm with Bryan, see if grounding the wire makes horn beep, while pushing the button.

[PeWe]

I had a horn that did not want to sound when I wanted.
It was the horn button, metal inside.
I opened that switch,
electrical contact cleaner spray and twisted the button while pressing it some made it to be reliable again. It must work direct in critical situations.

It can also be bad conductivity of switch-handlebar-upper tree-ground. Or corroded connection to horn. Measure the   wires to horn, one of them should have 12V.

[Mushman]

I should have clarified in my original post, the horn was working before. Taking Bryan's advice, I connected the black wires back together, ran a wire to the green one and grounded it...the horn beeped. I guess I need to move on to the switch and try PeWe's advice. Appreciate the help so far.

Brian