horn relay location

richardh · Postby **richardh** » Mon May 03, 2010 3:37 pm

Can anybody confirm the location of the horn relay in the 1993 XJS 4.0? I have the JDHT manual on CD and in shows the relay to be under the hood on the right hand side (drivers side in the UK). The diagram shows it as being the one nearest the firewall, but I find that the wiring colours on this relay do not match the wiring diagram info. The horn on my car has decided to announce itself unassisted! Very embarassing!
Cheers, RichardH

Brakebuster · Postby **Brakebuster** » Mon May 03, 2010 4:27 pm

cant help with the relay location

but the horn sounding on its own will probably be the contacts on the steering column under the steering wheel , above your knees , the contacts are very ' heath-robinson/ cottage industry' , and can easily break/come loose

this is however for the HE column, i dont know if the facelift has the same setup
BB

ptjs1 · Postby **ptjs1** » Mon May 03, 2010 5:18 pm

richardh,

The relay should indeed be on the right hand side under the bonnet. It's in a group of 3 that are all light blue and it's the one nearest the bulkhead. What colour wires have you got on the relay which are indicating that it's not this one? I guess it's possible that the wiring is transposed with, say, te one next to it. If you tell us what colours you've got in this position, I'll chck my own car.

Paul

richardh · Postby **richardh** » Mon May 03, 2010 8:53 pm

Thanks for the response gentlemen. Paul, the wires on that relay in my car are:
Pin 30 - Brown
Pin 87 - White/Red
Pin 86 - Yellow/White (thin)
Pin 85 - Blue (thin)
According to the CD Manual they should be Purple, Purple/Yellow, Purple, and Purple/Black.
Unfortunately (or fortunately) The problem has now disappeared. To avoid embarassment I have rigged up a dummy Horn fuse with a lead to a 10A fuse and switch. If it happens again I can immediately switch it off! There may be an intermittent earth somewhere but I need more time to chase it. I think I need to drive it more now that I have some time. I will look at the column connections as well. Cheers.

almcl · Postby **almcl** » Tue May 04, 2010 7:28 am

Those wire colours correspond to the starter relay.

It sounds as though someone has had the relays off the mounting bracket at some point and put them back in a different order.

One of the other two might be the horn.

richardh · Postby **richardh** » Tue May 04, 2010 10:41 am

Thanks Al, I'll try to check the others some time today. Richard

richardh · Postby **richardh** » Wed May 05, 2010 12:14 am

You are right Al, the horn relay has been moved to the middle position, confirmed by removing the relay silencing the horn. I've put it back where it should be. I'll keep my "jury rig" in place and see if the fault returns. Thanks.

almcl · Postby **almcl** » Wed May 05, 2010 1:23 pm

cant help with the relay location
the horn sounding on its own will probably be the contacts on the steering column under the steering wheel , above your knees
this is for the HE column, i dont know if the facelift has the same setup
BB

I think the airbag put paid to the 'knitting-needle-down-the-middle' arrangement with the brass tube, the nylon nut and those wonderful copper fingers.

I must admit I've never had the courage to actually look, but the parts cat shows a much different arrangement for facelift cars, with a slip ring and spring loaded plunger all mounted on the steering wheel itself. Just getting in there to investigate would frighten the life out of me, waiting for the bag to blow up...

ptjs1 · Postby **ptjs1** » Thu May 06, 2010 2:41 pm

richardh,

If the problem does lie with the slip ring and you need to take off the wheel then I can talk/describe the process for you. Also, if you need a photo of the slip ring assembley on the back of the wheel, drop me a line and I'll send you photos from a spare wheel that I have.

Paul