Lame Question - Horn Fuse
 

Sorry guys, this is probably ultra basic stuff but I can't find the horn fuse.

I took the aftermarket steering wheel off to reinstall the original. All can can see is the brass back of the steering wheel must touch the contact point on the long brass fitting that fits into the center of the steering shaft and has a clear white nylon threaded nut that screws onto the steering wheel to shaft nut.

I suppose when you push the brass plate on the wheel against the connector tab in the center of the shaft, the circuit is complete and the horn sounds. Well, not really....

I tried eveything so I think it just may be the damn fuse if I could only find it....

Test the circuit by earthing the contact in the centre of the plastic nut. If the horn sounds the problem is the contact from the horn-push on the wheel, or the earthing of the wheel.

There is a horn fuse, and it is unmarked on the circuit diagrams, at least for pre-facelifts! It is the fuse under the bonnet on the LHS. There are four there, and it is the one nearest the front. ON the diagrams it is shown as the auxiliary fab fuse, but it is also the horn fuse.

Greg

I have just been here. If the fuse is ok, remove the panel under the dash and if you look at the column almost above the brake pedal you will see 2 contacts on the column. These are the horn contacts, if you short these the horn should sound.

Let us know how you go. I had the steering column out over the weekend to fix the horn.

Forgot - Horn fuse depends on model year. my 89 has 2 horn fuses 1 for the supply to the horn and 1 for the horn circuit that drivers the relay.

If you have an XJS you need a manual. Go and buy the one on CD ROM it has all of this information.

Warren and Greg, Thank you. I would like to buy the service manual in the near furure. Right now, I have my hands full and cant jump into the total restoration of the car just yet. Im focusing on the basics for now. That damn horn is really eating away at me. It is a safty issue as I cannot use it while driving. Here in the suburbs of Philadelphia, its a necessity.

My car is also the 89 year. I will first jump the contacts under the colum and if it dosnt sound, start pulling fuses. Ive tried earthing the center contact but will try again as well as the under colum contact one last time. Its seems too simple to not work. I guess those are the hardest fixes.... lol!

Warren, I will look where Greg said the fuses were but where is the second one, or both on your 89?

There were two different horn circuits used on 1989 MY cars.


Click here for decent wiring diagrams. You really can't do much without 'em.

http://www.captainjaguarscathouse.co...ec%20Guide.pdf

Cheers
DD

Doug,

The linky doesnt work

The fuses are in the engine bay. 1 in the black and another in the white fuse box next to the horn/fan relays.

Did you short the terminals on the steering column?

yes, its a very simple method, although there is no direct contact of the brass backing of the pressure point at 8 oclock and 4 oclock where the horn icon is on the rubber wheel. It looks like you have to press the medalion in the center for contact. Either way, its a simple ground switch with the one side of the switch coming from the center of the steering colum and the other to ground.

I checked all the fuses under the bonnet (both black and white boxes) without finding a shorted one. I will tinker a bit more after looking at the "under colum switch" and try engageing the horn other ways.

If I cant find the problem, I'll post a picture to compare to your setups.

Sorry I was not clear in my last post. I was not talking about the terminals on the steering wheel, I was talking about the terminals on the column under the dash just above the brake pedal. This is where the horn exits the column.