Horn Button query

Can anyone help with the following query? I'm using z900 handlebar switches on a z650 rebuild, you can't get z650 switches any more. Everything is fine apart from the horn button, which doesn't seem to do anything, A24017ccording to the wiring diagram the horn is a black wire and sure enough there is a black wire going in to the switch. The problem is that pressing the horn button doesn't connect this black wire to any other wire entering or leaving the switch. I've disassembled the switch and the black wire is one of three attached to the horn/passing switch but pressing the switch has no effect on the connectivity of the black wire. How does the horn work?. Any help appreciated

Dennis

I believe that switch completes the circuit through the handlebar. If the bar is painted, that can be a problem.

That's right. The button completes the ground. The body has to have good contact with the bar. I have a relay in the system for my duel horns. The button it too wimpy for two horns.
Steve

I like to use black superbike bars on my bikes. To get the proper ground from that switch I simply run a dedicated grounding wire through the harness and ground the end onto the frame ground under the tank. Doing it that way I eliminate all the failure points designed into the stock system.