If the horns have been replaced, its possible to install them wrong (opening facing up) and have them get full of water. Also if replaced, some replacements have sketchy wiring between the horns. Also if any work has ever been done in the steering column and you don't have juice at the horn or signal at the relay... theres a delicate conection between the airbag and clockspring... a tiny lug on a black plastic tube can easily be broken and you end up with no horn. Just throwing out a couple scenarios to be aware of as you hunt for the trouble.