Horn works when steering wheel is turned (very annoying)

[rojakilian]

Hello Jaguar Guys,

what could be the reason for that? Any ideas?

Best regards


Robert

[Gfhug]

Robert, it would help if you told us which series car you have, S2 has different horn control to S1.
Add it to your signature. Sorry can't help otherwise

Geoff

[Heuer]

As he is posting in the S1 Forum I assume he has one of those?

Robert has a short in the steering column so I think he needs to disassemble the whole thing. SNGB sell a kit of parts although it is worth trying to reuse the originals, specifically the brass/copper parts.

There is a column restoration thread somewhere on the Forum.

[abowie]

It'll be a short somewhere inside the steering column. Which is easiest sorted out with the steering column on the bench.
Were it me I'd just disconnect it.

[Heuer]

First test is to remove the horn push and see if the problem still exists. If it does then solving the problem would be, as Andrew says, best resolved with the column on the bench.

This is what it looks like:




Suggest you dismantle the shaft and give everything a good clean. Basically the white ring clip sits over the shaft where the hole is. The small brass nipple fits into the hole, the spring goes on top and the brass collar holds everything in place. When the long thin inner brass rod is in place the nipple is in permanent contact with it regardless of rotation. The copper contact completes the circuit.



The original contacts were beryllium copper which is a good spring material. The new ones are regular copper, which is not. The BeCu will stay in contact, regular copper will relax to wherever it's held and not spring back. Hutsons sell ta repair kit if you need it. This is the repro copper contact to be wary of so try and reuse the original:

[rojakilian]

Hello again from Germany,

first of all many thanks for your answers.

Yes, its a ser 1 horn, therefore posting in the ser 1 forum.

As far as i could see from the wiring diagram, the horn works if you ground the earth wiring from the relay which opens and closes the strong wires to the horns . the relay itself has permanant current, but no ground until you push the centre of the steering wheel. Therefore the ground wiring from the relay to he column is insulated against ground.
now is the question what part of the arrangement fails - i suspect it could be the brass sleeve where the copper berrilium piece makes contact via the spring to the inner brass rod? or is it something else i have overseen?

Maybe someone has had just the same problem and i a can avoid to to take the column in and out until miracoulesly it works....

Kind Regards

Robert

[Philk]

I had exactly the same problem on my S1. In my case, it was down to the bottom bush in the upper steering column perishing with old age and causing a short as the wheel turned with the inner and out column meeting (it does not need much lateral movement at the wheel to cause a 2mm sideways movement further down in the mechanism). It is highly likely that your issue is down to a short somewhere in the upper column assembly.

[H7OB]

I had a similar problem except, in addition to play in the column, I had my wipers randomly go on the extremes of lock! It was a combination of the aforementioned bushes and a hole worn in the loom just above a splined section of the column.

I second David's tip on opening out the bushes a little. They seemed very tight without. Thanks to all, I also have lost that slightly un-nerving sensation that the wheel might come off in your hand, not to mention the 3 degrees giving it what-for round every tight corner!

[rojakilian]

Hello again from Germany,

the reason for the fault was the berillium/copper contact (as recomended i used the original one) which was making contact to the outer column .

If someone has the same problems, some explanation, now that i see clear:

There could be NO short cut in the circuit as you only earth the wire to the horn relay (W1), when you push the horn button.

I cant also be the failure of the bearings outer/inner column as the inner column itself is isolated to the ground wire coming from the relay. Ground contact for the relay comes from the wire, goes to the berilium/copper unit,(picture 3 post 5; 3rd from right) from there contact is made thru the brass ring (looks like a crown; 1 from left) this ring itself is isolated against the inner column via the plastic ring (2 from left) where the tiny spring (4 from left) sits in. earth again goes thru the small spring (ball pen size) with a little pin (3 from left) at one end. this pin again makes contact to the inner brass rod which itself is also isolated against the inner column (5 from left , 1 and 2 from right). only when you push the horn, ground contact will be made thru the grub screws to the inner colunm which is connected via another copper contact (4 from right) to the outer column and the car itself.
Sounds complicated, but isnt so much, when you see thru.

Best regards
Robert