Re: '84 capri, 16' horn doesn't work
If it's electric, hit it with 12 volts
Any noise it's good, no noise, time for a new horn
If it works with 12 volts, then start back checking your power with a tester or a lamp.
If it's air, there should be a small compressor in the immediate vicinity check to see if that runs when the switch is engaged. If it is an air horn, the culprit is probably the compressor, they don't last very long, especially in salt air
Also the rubber hose going to it may be broken