I am trying to get my horn to work in my 67. New horn relay, hooked up correct, horn works when hooked up to battery power. When I hit my horn button i hear the relay click, but the horn does not blow. there is power at the black wire terminal at relay, but nothing at the green horn wire when horn button is pushed. What could be the cause?

You should have a continously hot wire at the relay. The fact that you hear the relay click makes it reasonably certain the relay is working. See if this is the case using a test light. One end of the light attached to ground, the other probing the connections one by one.

alan

the terminal on the relay where the green plugs into should be hot at all times?