This problem happened a few times about 6 months ago, then seemed to fix itself. It happened again yesterday.

The horn randomly comes on by itslef, and will not turn off, except by turning off the ignition, or unplugging the horn itslef. Every time it happened previously, when we left the ignition off for a few minutes, then restarted the car the problem went away.

My guess is that there is a problem in the wiring in the steering column setup somewhere. Has anyone else encountered this problem. The car is a '94 Magna TS 2.6L auto.

Remove your horn button you might find it missing some spring. If it missing spring, I might have a spare one depending on type of steering wheel and colour of your steering wheel. :)

the horn system also has a relay
dont know where it is
but if the horn ring is ok ..
replace that relay

From what I'm aware there is no horn relay in poverty packs, only verada got a dual horn setup which needed a relay. So it fairly easy to fault find :) Most like something to do with horn switch :) But then again I might be complete wrong.

I have a Verada, the previous owner apparently had road rage as when I took the steering wheel apart the pad was cracked and parts moved about. in my scenario in summer the heat built up in the car, hornpad expanded and when I turned ignition on the horn would sound. If thats the case then Sparky is on the right track. remove your horn pad and check it out before thinking about pulling apart wiring.

I had exactly the same thing happen quite recently, as a stop-gap measure I took out the fuse (didn't think of it when I first pulled over, was trying to figure out how to reach the actual horn behind the bumper)

Couldn't see any issues with the actual steering wheel assembly. Got myself a Verada steering wheel and the associated assembly (need the whole blinker assembly), hasn't happened since, so don't know if it fixed the issue or has just masked it.

PS. when trying to remove fuses, there's actually a pliers/tweezers-like plastic tool built into the fuse box, didn't realise initially and took quite a lot of swearing to get the fuse out. Piece of cake if you use the tool.

OK I will take a look at the horn pad, but it all feels good. According to the wiring diagram, a '94 Magna does have a relay which is apparently located somewhere unser the center console. Because the problem seems to disapear after the ignition is left off for a while, I am suspicious of the relay. Does anyone know how to get inside the center console to access it?

Hmm, looks like you're right (page 1160 in the PDF). Can't be bothered trying to check mine at the moment, after finally getting it all back together after installing remote locking.

In a nutshell, start removing the centre console from the far back of the centre strip. There are two screws near the back of your front seats, then two screws under the ash tray; this will then allow you to pull the centre strip backwards and up a bit, allowing access to the screws for the console itself. Two screws hold in the plastic surrounding the stereo, but you may have already have uncovered the relay in question by then, dunno where exactly it's located, somewhere around there judging from the diagrams.

Dont forget the screws under the storage bin of the centre console :D