Under the hood horn fuse blowing when horn activated on steering wheel. Where is the horn itself located ?

The horn/s are located on front cross-member.
Note the horn wiring diagram. The horn relay should be located in under hood fuse box, remove the relay, use jumper wire between terminal 30 and 87, the horn should sound. If it does, problem on control side of relay/coil in the picture. Usually the problem is the horn button--wiring in steering column, maybe the clock spring? Terminal 30 is hot/voltage all the time. Use a test lite to check voltage. At the proper fuse, not only check the fuse, check voltage at the fuse circuit.

Every car model has a different location for the horn; but mostly toward the front of the hood.

unhook it in the steering wheel,look at the diagram on the cover,number 43

There is a relay for the horn, too. You can simply unplug that.

You didn't define your vehicle. Check the owner's manual for fuse locations.

Horn relays are found under the hood in a fuse/relay enclosure. The horn switch on the steering wheel is part of a low-current circuit that activates the horn relay. That circuit's fuse will be located in the interior fuse panel, wherever that is hiding!

2001 malibu horn fuse and relay are located in the under the hood fuse box.
location 21 should be the relay
location 43 should be the fuse.
if the relay is put in wrong the horn will not work. if you replaced the relay and the horn stopped working try pulling the relay out and turning it around. and try the horn again.

CHECK for bad grounding of horn itself, rust and oxidation may not allow it to ground, also try "jumping" a wire from battery to horn, if it blows horn itself is good, contacts inside steering wheel button may be bent flat, or wire bad..

On the bottom left of hood you will find the horn or you may remove the horn relay.

I have or should say had same issue on 1996 cirrus quick fix just remove the HORN RELAY located on the left side of dash relay only controls horn. To really solve the issue at hand you must replace the clock spring on the steering wheel dis-arm air bag before messing with steering wheel to avoid activation of air bag disconnect battery for 10 min then its safe to fiddle with steering wheel safely.
Chino S.G.V

Yes prb the fuse. Look under the drivers side by the break in the car. It may have a cover over it. They usally have a diagram of what fuse is what. Also under the hood is a bank of fuses. It will be towards the front on either the left or right side under a black cover.

a very common cause of this problem is the steering wheel mounted horn button looses it's connection to the horn circuit due to a defective ribbon rotating contact under the steering wheel, the special clock spring shaped ribbon wiring harness is what allows you to turn the wheel and still have a connection to all steering wheel buttons and the airbag, to check this listen for a click when u press the horn button with the engine off, it will be faint but if u listen closely u will hear it, if u don't hear it u will ned to replace the Clock-Spring rotating contact under the steering wheel. I am a Ford factory trained tech with 20 years of new car dealer experience.