horn circuit

I bought a used vf 500f interceptor 86 about 6 months ago and have been getting it running, it didn't come with a horn so I bought a new one however when I plugged it in and pressed the switch I got nothing. Im not sure what the problem is, my lights all work so it's not the fuse and I've taken apart and cleaned the switch and it seems to be in good condition. If anyone has had experience with this and know a solution, please help.

 

check that you're getting 12 volts at the switch contacts.

 

I checked with a voltmeter and I don't appear to be getting anything between the switch contacts

 

Are you getting power to the switch. If not recheck fuse, then check and see if you are getting power to the fuse side?

Usually the indicators and brake lights are on the same circuit. Do they Work?

Green/white will be power from the fusebox.
Think power to fusebox is red/blue (or black,,) from ignition switch
power to horn light green,
earth dark green