steering column grounding for horn?

[tedtaylor]

Late federal Elan Sprint DHC
My horn works great.....except when the steering wheel is dead center, which is the ideal position while driving straight down the road. I've pulled apart the button and wheel hub and everything is working as it should. I have full power to the lead and contact, however the center column (which the wire grounds to via the horn push and brass ring mechanism) seems to be dead or not grounded in static center position. as soon as i turn the column (steering wheel) a degree to either side (L or R), it works!
Very frustrating when you are driving down the road and try to use your horn and the only way it works is to move the steering wheel.
Can anyone "steer" me in the right direction here on what to look for or where the column is grounded further down from the hub?
thanks
TED

[archigator]

I had a similar problem, with my horn going off at inopportune times... especially when I would pull up behind someone at a red light. (I made sure I never pulled up behind a motorcycle gang.) It all came down to one of my horn wires being mashed flat and pinched by the steering bracket under the dash... causing a short.

Just a thought...

Gary McGraw
71 Sprint FHC
Miami, FL

[rgh0]

You should have an earthwire across the steering column flexible joint to the rack pinion and then an earth wire from the rack body to the chassis. if all that is working and your rack is in good condition the centre column should be always earthed. it sounds like you may have wear on the rack or pinion so on straight ahead you dont have good tooth contact and the needed earth path.

cheers
Rohan

[wotsisname]

I'm thinking the coupling rubber may be perished and providing a route to earth except in the straight ahead or that the connecting cable [if fitted] is broken inside the outer sleeve..
If you can get it to not work, then test for continuity at various points you should be able to eliminate a few of these thoughts.

[LaikaTheDog]

cracked contact ring behind the boss

[tedtaylor]

cracked contact ring behind the boss

all the horn boss and hub ring are just fine. with it off, i'm able to use a test light and that's how i'm able to determine that the center spline is not grounded at top dead center, only when i turn the center spline left or right does it ground and make contact.
I just don't know where the center spline is supposed to be grounded elsewhere or further down the column. none of the pictures/diagrams i've looked at show it either.

[wotsisname]

Re read Rohans post. Test continuity between the horn ring and the rack mounting earth.. if that fails then try the same for the column just above flexible joint to the rack mounting earth... Etc. The column shaft itself is the Conductor.. I hope this makes sense

[oldelanman]

This pic shows the steering column earth wires that Rohan refers to - abeit RHD but I would think LHD will be similar.

[tedtaylor]

Roger and others, thank you! I found NO ground strap between column upper and below the rag joint, so i made a "jumper" and connected. Success! My horn now works flawlessly at dead center going down the road, so that was the problem and solution!

[alan.barker]

I would suggest using braid to make the earth which is more flexible.
I think the replacement ujs for the steering are now all metal so they do need the earth braid.
Alan

[billwill]

I would suggest using braid to make the earth which is more flexible.
I think the replacement ujs for the steering are now all metal so they do need the earth braid.
Alan

They have non-conducting grease in the rollers of the U/Js so it is probably best to include the ground wire in any case.