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Of horns and steering column grounding

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drooartz

drooartz

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So I was checking the Tunebug's wiring tonight, and I'm having trouble getting the horn to work.

I've checked that I've got good wire runs to the horn itself (harness was new as of 4 years ago). Horn works if I run wires directly, or if I run a direct wire from the ring on the steering column to a known good ground.

The problem seems to be in the connection from the steering column itself to ground. In looking at the diagram and the mechanics of it all, it would seem that the horn works when the ring is grounded. The horn button would also seem to be grounding this through the steering wheel hub and on to the column.

If I run a continuity test from the center of the column to a ground, there is *no* connection. It is acting like it is not grounded.

What am I missing?
 
I just checked mine, and the steering column that the wheel attaches to is NOT grounded????
Scott in CA
 
I remember a little wire inside that collar surround needs to be attached inside...
 
My understanding is the ground side of the horn has a wire which attaches to the steering column plastic surround with the copper face. The steering wheel has a spring loaded plunger inside that is insulated from the wheel. The plunger rides on the copper face. A wire connects the plunger wire to the horn push which grounds the horn ground to the steering post. In my case and in Drew's, the steering post is isolated from ground, thus our horns do not work! How is that for a sentence! Anyone else have this problems, and what did you do about it? Sound like what I screamed across the room to my wife on the phone when I had that terrible pain in my right abdomen, later an appendectomy was performed!
Scott in CA
 
smaceng said:
My understanding is the ground side of the horn has a wire which attaches to the steering column plastic surround with the copper face.
Click to expand...

I think you know what you meant, but got that the wrong way round. Assuming the car is still pos ground; the copper face (slip ring) is the negative supply from the battery and as you say the power goes from the slip ring, up the the sprung pillar and through the horn button.

Then the spring wire on the outside edge of the horn button pushes against the inside of the steering wheel boss (which must have a metal can inside it to complete the circuit to the column, I can't quite remember that bit!) and then down the column to +ve/ground.

Try putting a bit of wire from the slip ring to the column (in effect holding the horn button down) then touch a wire from different bits of the column/rack to a good +ve/ground and see when the horn blows, then put a permanent wire in to make the circuit. Don't use the pinch bolt for this or you'll have to coil the wire up round the column as you steer :smile:

I don't recall having to put a wire in to ground the rack, but maybe the rubber mountings are insulating it from ground?

John
 
Good idea, John. I'll give that a try.
 
My 65 has a little cable from the steering shaft to the rack bolt to ground the shaft. Supposed to twist up and untwist as you steered. Course its broken and the horn still works.
KA.
 
nomad said:
My 65 has a little cable from the steering shaft to the rack bolt to ground the shaft. Supposed to twist up and untwist as you steered. Course its broken and the horn still works.
KA.
Click to expand...

I would guess some PO added that wire?
I'm working on getting mine hooked up again too. Just ordered a new brush from VB yesterday
(BTW, I called a few weeks ago to when winter sale prices ended "through March".....wrong; I was not pleased, oh well, the order shrunk very fast.)

During dash redo and fit I kept hearing a click from the relay (I added) it was the slip ring touching column so I think I've got a circuit, why the horn didn't blow and the relay just clicked is likely another can of worms.
I do have some work ahead to get the column centered in the hole in the housing too.....suddenly an old school squeeze bulb horn hanging off the side looks like a good idea.
 
Sorry, that was the problem with mine - I had to solder in a new little wire.

I've heard of this happening before though - what was the factory method of grounding the column?
 
I was hoping answer would develop here. I put in a new horn push on my 65 from Moss. The horn works but only when the steering wheel is turned certain ways. I have taken it apart numerous times and sanded the copper collar still the same results.

Mark
 
I was thinking of putting a skinny marker or something in the hole and turning the wheel to scribe a mark on the ring, to check alignment....
 
If your horn push is making a good ground with the unpainted inner part of the steering wheel, the ground problem is most likely a freshly painted steering column and/or steering rack.
Think about how the steering wheel is mounted.
It has a rubber collar under the dash to isolate it.
It bolts to the steering rack which has (or had) paper gaskets around the mounting clamps. And the rack is mounted to the steering arms which are isolated from the chassis by rubber bushings via the A arms.
Now if you painted all those parts, there is no ground from steering column to chassis. There never was a good ground from the factory but lack of quality paint and some bare spots did make for a ground.
This seems to be a common problem on fresh restorations.
 
If a PO fitted a grounding cable on my 65, with 35K original miles, that I bought 2 years ago with 1976 inspection stickers, out of a barn, he did one heck of a job of making up something that looks 100% factory! Anyone got any original factory pics? Horler?
Kurt.
 
Got a picture of it?
 
Unfortunatly, jv, I have the worlds slowest dial up and admit to being barely computer literate. Otherwise I'd take one and post it. When my college student son comes home I'll see if he can and post it to you. I am pretty sure its factory. About 1/16 steel cable with crimped on end's that are attached under the steering shaft to rack clamp bolt and to a bolt that attaches the rack to frame.
Kurt.
 
Here is what I just did:
I connected a wire from the frame at the steering rack mounting bolts to the rack at the cover on the front side of the rack. Difficult to get it all in, but I hope you get the idea. I would have liked to do what the factory did, but I would also like the horn to work. I found that the ball joints did not pass the gound, thus prevented the rack from being grounded. Could just leave the paper things off the rack mounting clamps. Always wondered what that those were for? The steering shaft is now grounded and the horn should work when the steering wheel is installed. Thanks for everyone's help.
Scott in CA
 

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Thanks again for the tips and pictures. I'm going to play with this more tonight. I've got some good ideas now, just need some time to play.
 
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