I just bought a 1993 jeep wrangler 4wd. The only thing is the horn isn't working. How can I fix this?

how to fix a horn on the work bench
or how to diagnose a dead horn on car.?

my guess, #2
TJ car.
here is the list;

1. do not fiddle wires near horn sitting at steering wheel unless you defeat air bags first, per the BOOK "FSM" or u may die.
2. check the fuses first.
3. scan the PCM next, got DTC errors ?
4. read the FSM yet?

here, TJ
http://colorado4wheel.com/manuals/Jeep/TJ/

the pdf.
chapter 8H> horn
and the schematic there 8w?
8w41-3 see that relay, does it click with button pushed?
key on?
need more ask.
is ground good to horn
did you hot wire horn to see if its really good first
connector pulled?

In the fuse box under the hood near the battery.

Check the horn ground. By pass the relay and feed the horn at the relay terminal. Could be a bad wire from the relay to the horn.

my horn quit working on my 99 wrangler...took it to a shop...the part they changed was called a clock switch...very expensive part but it fixed the problem...part was supposedly dealer only part...horn works great now

So you are assuming the board is bad.....Jeep gauge clusters are notorious for problems at the plug behind the board. Sometimes you can get it working just by giving the dash a good whack with your hand right above the gauges.(not kidding) If that works, best thing to do is remove the cluster and spray contact cleaner on the pins and contacts.. In extreme cases you can slightly twist the pins very slightly to make them fit tighter. (last resort).

you might try checking the linkage on trans case shifter. may need adjusting. might not be getting fully engaged

check the shift motor on the axle for holes. sometimes the rust through. i've fixed holes before with dura-glass body filler. if there are know holes,remove the shift motor to check and be sure the shift fork is not broken.

There is now bus signal to the Insturment cluster I have seen this before. Unplug the Insturment cluster and plug it back in this will reset the computer it should communicate with the Can C bus and should come out of gear. Keep in mind if this works it is only a temporary fix. Hope this helps please rate if it does.

Just a guess: wiring harness.

Sorry, but my solution would be to take that drive back to the dealership, if he has a warranty. This is a hands on type deal, you have to trace everthing with your hands. Now it sounds to me like it could be in the electronics. You have to go to the differential, find the vaccum lines, if equipped, some are not, then trace them back to the motor and make sure they aren't cracked or broken. I hope this solution was helpful, please rate. Thanks