The 40 amp fuse #14 in the underhood block supplies power to that section of the fuse block. The 20 amp fuse #13 in the fuse block supplies power to the horn relay. The horn button supplies ground to activate the horn relay through the body control module.
most of the time when we see an inoperativ horn in that vehicle it's the clockspring. (the thing behind the steering wheel that completes the circuits to the horn switch, cruise buttons, airbag, etc. while allowing the steering wheel to turn).
Best of luck!
