I have a 69 Firebird. The horn won't work. I installed a new relay which clicked when I pushed the horn button indicating it was working but the horn wouldn't sound. So I switched some wires on the relay and then it stopped clicking. Off the car I can jump what must be the #85 and #86 terminals on the relay and I get the clicking. However when the relay is so initiated, jumping #30 and #87 terminals there is no continuity. On a cheap universal relay, I get the click and continuity following this procedure.

So before I fry another expensive relay I want to be sure I wire it correctly. I went back to a thread on this site from 2012 to get a colored wiring diagram. One pair of wires is in a dual plug that will only go on one way. That leaves me with two black wires with pink trace. It leaves me with two terminals on the relay of course. My issue is that one of the open terminals is either #85 or # 86 which energize the relay allowing current to go to the horns. So which wire goes there? One of them is constantly hot and the other is not. I assume that the wire that is not hot must be switched power and would go to the #85 or #86 terminal which ever it is. This is the middle terminal on the relay. That would leave only one terminal open for the hot lead which must be either #87 or #30.

Any help would be appreciated.

You sure the actual horn work? They often stop making sound. Did you put direct power to them?

Thanks Bob,
Yes the horns both work when they get power.

The wiring diagram shows a dark green wire that goes back to the firewall plug where it changes to a black wire that appears to be the horn switch. I haven’t heard you mention any dark green wires. It appears the horn relay is also used for a buzzer. Are you sure you have the correct relay?