horn doesn't blow when horn ring is pushed

Most relays have two sides, switch side and control side. If you unplug horn relay, use jumper wire between the two terminals on the switch side of relay, the horn should sound, does it? The wire that goes up steering column is ground for control side of horn relay. Jumping the switch side of horn relay bypasses the control side, just to see if horn will sound. You could do actual testing at the horn itself. If one wire, that is voltage, and the horn grounds through the metal body. If two wires at the horn, one should be voltage and the other ground. You could use jumper wires off the battery for voltage and or ground, just to see if horn will sound.