Horn on my 72 just quit working.

use a test light have someone honk the horn while holding the test light to the horn wire. does it light? if so make sure you have a good ground. if no check fuse then check relay if not sure which fuse check them all not that many,

bench test disconnect the wire going to it run a wire from the battery to the horn and touch the connection. does it work? if no check ground or add a ground wire lather rinse repeat. still no replace horn.