How to ground the stearing column, S2 68

[Adde]

Hi
I need some advice and guidance as I have tried to troubleshoot the horn in a Lotus Europa S2 68. I have come to the conclusion that there is no ground in the steering column.
I don't know the reason for this but I suspect that there is no ground strap across the steering racket (see attached picture , borrowed from http://www.lotuselan.net/forums/lotus-electrical-f38/horn-help-t26549.html).
However, how do I access and fix this? It seems to be quite tricky to access, or?
Is there any alternative way that I can ground the steering column?

Regards/
Adde

[TCS4605R]

The S2 wiring diagram shows a Purple w/ Black wire from the horn to the switch at the steering column, then a ground wire from the other side of the steering column to earth.  What your picture shows is probably a fixture by the previous owner because he could not figure out the proper grounding means.

Tom

[jbcollier]

The rack is solid mounted on a Europa.  Just need the "wire bridge" as the rubber in the coupler can insulate the column from the rack.  I have an S1 so can't advise you about access on an S2.  First run a jumper from the column to a known good ground and try the horn.

[StephenH]

My S2 has a 2 stage horn, intermittent when engine stopped, very reliable when engine running, just needs those extra vibrations to ground the column shaft

However I think the 'wire bridge' is a good idea so I will have a peer under the car and see if I can add the same feature.

[Grumblebuns]

my S2 has a large support collar under the steering column. That collar is then bolted to a "L" shaped bracket behind the dash. With my fingers I can feel a couple of wires bolted to the bracket. I'm assuming that those wires are for grounding things behind the dash and possibly the horn . I don't see any jumper wires on the column itself.

[Lotus 47]

The original Triumph joint has an earth wire bridging each side of the joint. The joint has rubber isolators so it will not carry current. This joint is rubbish. I find they wear out and provide play in the steering. Use the later style coupling with a universal joint. It conducts current as well! Win! Win!

[Adde]

Hi.
First I would like to thank you all for the responses, but I still have some more questions. Which mainly is how to access to check and if necessary to fit a wire bridge across the joint. The question is if I should access it from underneath the car, or from the hood or from the driver seat?

1) TCS4605R:
I agree that there is a purple w/ Black wire from the horn to the switch at the steering column. But my understanding is that the steering current should be going through the steering column all the way down to the joint "lower steering racket" and across it through I ground wire bridge. After that the current is grounded in the front wheel frame/car body.

2) jbcollier:
I will remember that it worked when I ground the steering column, but I have to check it once more next time I'm at the garage. However it don't work if I just ground the support column. Most likely I need to check the ground wire bridge, but I still haven't figured out how to access it without having to disassemble too much of the car as it seems to be hide inside the beam. The question is if I should access it from underneath the car, or from the hood or from the driver seat.

3)StephenH:
Unfortunately, in my case the vibrations from the engine running is not enough from grounding.

4) Grumblebuns:
I don't think that the steering column is connected to the steering column. At least not in my car, hence will it not be enough to ground the support collar as was suggested. Should it be connected?
I guess that the wire you feel behind the dash is ground for other instruments but not the horn. The tricky thing with grounding the steering column in the driver seat/cockpit is that the column is turning. But you can of course do a little less attractive solution, maybe i should start with that to pass the car inspection.

5) Lotus 47:
I will consider to change to a universal joint in the future, but until then I intend to use a wire bridge to see if it solves my issue. The question is how to access the joint...

Best Regards,
Adde

[Gmg31]

I'm re fitting mine this week and I plan to add a short earth stap from the collar to my earth bolts on the tunnel, I can see absolutely no benefit to the earth bridge in your photo especially when you discover how hard the knuckle joint is to access. Keep it simple.

[jbcollier]

The steering shaft runs in plastic bushings.  You need the wire across the stock u-joint or the shaft will not be grounded.