A couple months ago I fixed the same problem with the horn in my 95, below is a rewrite of a note I posted on the repair.

Fixing 850 horn contacts behind air bag

Symptoms:

1) The horn does not work, or works when pushing on one side but not

another. This can go from works fine, to works on 3 corners, then 2 corners,

etc. as more of the contacts break (see below). Or the horn might work

intermittently, or just a tiny beep.

2) The horn will not turn off (you can't miss this one!)

There are 4 horn contacts inside the steering wheel. They go thru a metal

frame and are held in place and insulated by red plastic around each

contact. The contacts normally sit just below a piece of metal on the back

side of the airbag, so when you push on the horn it touches at least one of

those contacts and blasts the horn. This makes sense when you see it.

In my car the plastic that holds one of the contacts in place cracked and

allowed the metal contact to move just enough to touch the metal frame,

making a permanent circuit. Thus the horn was always on. Most reports I've

seen say the horn doesn't work right, I guess in that case the contacts

completely fall out or otherwise are not where they need to be to complete

the circuit.

Details for the fix (from memory)

- make sure you have your radio code

- disconnect the battery

- turn the wheel 90 degrees one side. There is a hole on the back of the

wheel, inside the hole is a t-30 torx screw. Remove it.

- turn wheel 90 degrees to the other side. Remove torx screw.

- airbag is now loose. Unhook electrical connector and put airbag in a safe

place.

NOTE: Do not turn on the key with the airbag removed. It will set an SRS

fault

code, you'll need a dealer to clear the code.

- Poke around for a while with an ohmmeter to figure out how the whole thing

works. Maybe it'll be obvious to you.

- look for broken red plastic parts. They are on the back side of the frame,

kind of hard to see, you can see the contacts sticking through toward you.

If they all look good try jiggling them to find a loose one.

I used epoxy to glue the broken part in place. It still had plastic around

the edge of the contact so I didn't need to insulate it from the frame. If

the insulating plastic around the edge is gone you would need to put

something around it for insulation. I didn't need to do this but imagine

shrink wrap or lots of other things would work.

I would test the connections with an ohmmeter before the epoxy dries,

especially making sure the contact is isolated from the frame you glued it

to. Otherwise the horn will be on all the time.

If you can't glue/fix the broken part and your problem is the horn honks all

the time I've heard you can remove that contact or I supposed tape it up and

stick it out of the way. Then your horn will work on the remaining corners.

Standard disclaimer about airbags and such - you have to remove the airbag

to do this job, it's up to you to decide whether you want to mess with that.

I am not an expert at this stuff. The Haynes manual shows how to remove the

airbag in the section on removing the steering wheel. Knowledgable people

say you shouldn't put an ohmmeter across the airbag contacts. And finally my

own tidbit - don't let your torx bit roll down the top of the steering

column, you'll never find it.

I would also educate all drivers of the car on what to do if the horn gets

stuck on. My wife was very unhappy when this happened to her, in the middle

of holiday mall traffic. If it is not raining the easiest thing to do is

remove the fuse (shares fuse with windshield wipers). Also familiarize

yourself with how to disconnect the horns. It's simple to do but easier to

figure out in a warm lighted garage than on the side of a dark road in the

rain.