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MG MGB Technical - horn contact diagram?

I removed the horn button and found nothing behind the button for the horn. I think there is another ring that may be missing and the wire to it. I ordered and received the spring contact that goes from the button down but what else is there? If I look through the hole in the steering wheel (behind the button) there is nothing. The horns are by the grill and wires run from them, but what is between that I am missing?
Thanks! This bbs is always a great source for everything! Yes, I did check the John Fowler Repair Manual but found nothing helpful. A exploded diagram image would be most helpful.
kids1

I should have said that this is a 74 Chrome B.
It has the fat rubber horn button.
kids1

Nope. That sounds like it. The horn push and the brush unit are all you will find. The combination of the horn push, brush and steering column complete the circuit.

Beyond that, there should be a contact point at the bottom of the hole for the brush unit. I'm thinking it's connected to a purple wire.

If you're having problems with the horns you may want to check the archives. I've just sorted out my horn problems.....almost. I got the high tone working and that was well enough to pass inspection. I think the low tone has given up the race.
Brad Batchelor

Brad, The brush unit does not have anything to contact below the steering wheel. I removed the side covers and can see the wiper arm and turn signal arm but nothing between those and the steering wheel. I think I am missing a ring with the wire to the horns etc.
kids1

To add to Brad's comments, there is a slip ring attached to the bottom of the steering wheel hub. The clamp for securing the turn signal switch has a spring contact that contacts the slip ring. A purple/black wire is atteched to a spade on the contact. The p/b wire goes through the turn signal switch wiring harness to the horns. To check horn operation you can use a clip lead to ground the P/B wire at the horns and move back toward the hone button if they are ok when the ground is applied. Just be sure to groungd the P/B not the purple. Clifton
Clifton Gordon

If I remember ....there is the horn button ...under that you will find a pencil shaped clear tube with brass buttons on each end and springs in the center of the tube pushing out on the brass ends...this runs through the hub and rests on a brass ring attached under the hub which floats on the contact spring in the steering column just inside the shroud where the hub attaches.
Sounds like you are missing the 4 inch tube which makes the contact when you push the horn. This is for the factory horn and hub...are you using an aftermarket steering wheel?

Tom
Thomas Koch

It is the factory steering wheel. I have the clear tube with the ends and spring in the middle. I don't have the ring under the hub or the lower contact spring that you refer to. If there is something that the lower contactspring conects to, I don't have that either. My purple/black wire comes up the column and is attached to the wiper arm. Sounds like I am missing a couple pieces.
I tried catalogs with no luck.
kids1

Try some junk yards. I'm lucky, there is a local yard here that has about 10 MGs (at last check) being slowly reclaimed by the earth and another 10 or so sitting in this one man's yard. Although, he treats each and every car like a prize. It's really a shame, he has some nice cars that are slowly sinking into the ground. I really hate to say this, but he's getting up in age and hopefully one day his heirs will let go of some the cars and parts before they are totally useless.
Brad Batchelor

Brad, any chance you could grab what I need, next time you make a trip to the junk yard? The yards around here have nothing older than mid 80s stuff. The stuff I seem to need is the same from 72-76, I think.
kids1

The other contributors have given you the correct information, but if you are like me, it isn't always easy to understand. I just fixed the horns on my '72B last weekend and will contribute my 2 cents worth. If you look through the hole in the steering wheel behind the horn button (where the brush that you bought sits) and you see nothing but air, then the brass/copper ring that should be on the back of the steering wheel must be missing. You should see a piece of copper colored metal blocking the hole. If you pull the cowling off the steering column (I have to drop the steering column to accomplish this) you have free access to the turn signal and wiper switch assemblies. The connection for the purple/black wire is on the same side as the wiper switch, but this is actually, as Clifton said, part of the metal semi-circular piece that holds the turn signal switch to the steering column. The thin curved metal piece that delivers the power to the circular brass/copper strip that should be on the back of the wheel is part of this assembly. I just looked at the Moss catalog. The do show a "slip ring assembly", part #263-755 for 71-78B's. If you have the contact for the wire, but the contact to the wheel is missing, you may need a salvage part. I didn't see the piece in the Moss catalog that holds the wiper switch on.

I took the wiper and turn signal switches off when working on my horn problem, but I didn't take the steering wheel off so I don't know how the slip ring fits into all of this. My own problem was that the contact to the back of the steering wheel was dirty. Running a piece of fine sandpaper between it and the ring did the trick.

I hope my 2 cents worth helps.

glq Greg

Thanks Greg and others. I am missing the "contact to the wheel" as well as the slip ring assembly. Obviously, this is why the original owner had a button installed in the consol to activate the horn. Anyone with a "contact to the wheel" or access to one, please feel free to email me. Thanks again everyone.
kids1

Is it possible that you have a horn button on your direction light stalk. You said that the purple-black goes to the DL switch Some of these switches you just pushed in on the stalk to give a hoot.
conrad sanders

conrad, I wish it was so. But this is an early 74 and had the horn button only in the center of the wheel. And yes, I tried pushing the switch in. No luck.
kids1

Does your last comment mean that you do have the slip ring piece? If so, you might be able to make the part that makes contact to the wheel. The original one is a thin piece of copper that is about 3/16th of an inch wide at the top, tapering more or less to a point with a round thing like the tip of inginiton points soldered to the end.

If you can find a fairly thin, springy piece of copper, cut it to size, solder a piece of copper electrical wire to it (8-12 guage) to provide the heavier contact surface. If you have the piece with the spade plug for the purple/black wire to plug in, you should find a place to pop rivet the replacement piece described above.

Bend the flat copper piece so that when installed, it will make firm contact against the slip ring on the back of the steering wheel. You will probably need to remove the wiper and turn signal switches to accomplish this.

Good luck.
glq Greg

Sorry, I misread your previous comment. You can apparently order the slip ring assembly from one of the parts houses.

glq Greg

Greg, yes the slip ring I can get, if it is the ring that mounts to the back to the steering wheel. I do have the base of the wiper switch which holds the contact for the purple/black wire. I just didn't know what went between the base and the slip ring but I think you described it. Thanks! I may even try to use an old piece from a set of distrib points I have off an old chevy.
kids1

This thread was discussed between 27/05/2004 and 02/06/2004

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