Horn doest work - 2012 Jeep Wrangler Sport Convertible SUV 3.6L V6 4x4 6-speed Manual

Disconnect the horn wiring at the horn. Check for voltage at the horn when the horn 'button' is pushed. If there is voltage at the horn, the problem is the horn has died. Remove and replace. No voltage at the horn is most likely related to the horn 'button' but could be wiring. Could also be corroded connections at the horn wiring.
Just had to replace the horn on a 2011 Chevy.
A 1930 Model A horn still works though.

The horn relay primary receives + full time and is actuated by receiving ground (-) from the horn button. Check ground continuity at the horn button (at the steering wheel) to make sure it is working first (most likely culprit). If the horn button is working, check to see if the horn relay is working (second most likely culprit). To test the horn relay, provide chassis or battery ground to the (-) primary terminal of the horn relay and see if the horn honks. If it does, that will tell you that the problem is in the wiring between the steering wheel and the relay, most likely a disconnected wire at the steering column.
The only other components in the system are the fuse for the horn circuit (if you have 12v at the horn relay, that is fine), and the horn itself. My bet is on the horn button pad itself.

Still check the voltage if it is below 12.7volts. It may be too low to have the car started. It is odd that the other electrical does not work. You may have to inspect all of the fuses then. If the fuses check out OK you may have to inspect the wiring. Check the wiring. After the battery the power cable should go to the boxes for the fuses, the relays, etc. Inspect the terminals there up to the inside. There may be some ground wires that are not connected or insulation or wires that may have gone bad.

There will only be one fuse for the horn. Find and check the horn relay. If that works check the wiring and the horn switch..

replace the horn or check wires leading to and from your existing horn.

The ignitors (ignition module) in the distributors tended to fail in early nissans and sometimes the best way to fix it is to replace the whole distributor with a new remanufactured one. One thing that can cause the ignitor and ignition coil to go bad is to crank the engine with the distributor cap off or the spark plug wires disconnected who told you theres a distributor fuse there isnt one

Could be bad horn or relay or the horn'button'.Start at the horn with a test light.Have someone push horn button and check for power at the horn.If no power then trace wires to relay,check for power cominginto relay.If power is going in but not out to horn relay is problem.etc. Some horns have a lttle knob you can turn to adjust them and get them working

it may be your clock spring. if your fuses aren't blown try the clock spring. you can get the directions online and buy the part from the dealership. it takes maybe thirty minutes but saves you lots of money. another easy way to tell if it is the clock spring.....does your cruise control work? if not the clock spring is bad.

Maybe horn became unplugged. Put 12 v power to horn make sure horn works. Put test light on terminal on horn have someone press the horn button, if light comes on and horn does not blow you may need new horn. if light does not come on you may have bad contact at horn button, blown fuse, broken wire, bad horn relay or possibly just a bad ground.