CA77 horn wiring connections - Help!

Bob15 · Post by **Bob15** » Mon Sep 14, 2015 9:23 am

My CA77 had no horn when I bought it so I picked up a working horn and am now trying to figure out the wiring. I've got the black wire from the horn switch coming down through the handle bar and think that attaches to one side of the horn. But I have no second black wire behind the horn mount to connect to the other side of the horn. I'm probably going to have to run a separate new wire to wherever it should go to pick up power.
What I am trying to find out is where this new wire from the other pole on the horn should go. I've studied the wiring diagram but still can't quite make it out. wiring is not my strongest thing !
Any useful info would definitely be appreciated !
Bob

Seadog · Post by **Seadog** » Tue Sep 15, 2015 2:14 pm

Bob, the wiring for the horn is in the wiring harness. two wires should be hanging down in the area of the horn for connection. Wiring for the switch should be within the handlebar and connected to the main harness in the headlight bucket. Has that been cut out?

Snakeoil · Post by **Snakeoil** » Tue Sep 15, 2015 3:16 pm

Don't have a CA77 wiring diagram handy. But I suspect that all these bikes are the same wrt the horn.

The first reply is what you should check for first. But given that anything could have happened to this bike over the years, you should have a black wire coming from the button on the handlebars. That is the ground wire and the button connects that wire to ground via the handlebar. The other wire is the hot feed and should go to the IG terminal on the lighting switch or igntion switch, whichever is appropriate for your bike. If none of the original wires are there, you could pick up switched +12VDC elsewhere on the bike, like the =12VDC terminal on the coil.

regards,
Rob

DianneB · Post by **DianneB** » Tue Sep 15, 2015 4:29 pm

On mine, one horn wire comes from the harness from the handle bar and the second comes from the main wiring harness and may be some distance away inside the frame.

*** CORRECTED ****

jleewebb · Post by **jleewebb** » Tue Sep 15, 2015 4:45 pm

on my bike I'm pretty sure a hot wire goes to one side of horn, wire from other side to horn button which grounds to complete the circuit when you push it...should be a dream wiring diagram here somewhere if you look...

DianneB · Post by **DianneB** » Tue Sep 15, 2015 5:40 pm

My mistake! The wire from the main harness IS the hot wire and the one to the horn button becomes a ground when the button is pushed.

Bob15 · Post by **Bob15** » Wed Sep 16, 2015 8:38 am

Seadog wrote:Bob, the wiring for the horn is in the wiring harness. two wires should be hanging down in the area of the horn for connection. Wiring for the switch should be within the handlebar and connected to the main harness in the headlight bucket. Has that been cut out?

The wire from the horn button is there but the hot wire has been cut out. I think I'll need to run a new one but am trying to figure out the correct place to pick up power.
I may try and pick up power from the coil as suggested above to see if that will work.

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CA77 horn wiring connections - Help!

CA77 horn wiring connections - Help!

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