the horn relay on most cars is under the hood in a big black fuse box the box should be on one of the fender wells. there is a lebel on the under side of the lid which tells u what relas and fuses are there. it may also be under the dash left of the brake pedal.same labeling
The relay for your horn is going to be under the dash in the fuse box. If it is not there, you will find it under the hood in the fuse box. Your car has 2 fuse boxes so just check both of them.