98 savana, horn honking all time

it's been raining alot and suddenly from my parking lot the horn in the van went off, i had to disconnect the battery to stop it.
i reconeccted and it's start again even when i turn on the van, i couldn't find the fuse to unplugg it.
please help

it sounds like a short in the wiring to the horn take look at all of the wires going to the horn and make sure that the sheathing isnt worn off the wires and grounding out and also make sure that there is no green on any of the connectors to the horn itself and wherever else the wires from it go