starter working now, but horn ring still "live"&horn wires _are_ correct...

I had problems with horn wiring... Here's what Speedy Jim wrote to me:

The jumper around the rubber coupling completes the path to ground thru the steering gearbox gears. All this means is that the horn ring is grounded. When the ring is pushed, it sends ground to the column outer tube. The outer tube is not attached to the chassis. There is a wire at the bottom of the column tube which picks up that ground signal and sends it to the relay.

Jim

thanks for _trying_ to help, mel, but wiring diagrams aren't what I asked about. the question (repeated) is:

I checked all the horn wiring on my 71 ghia, and it's correct (per bentley wiring diagram). horns both blow (when key is on). however, when I run a small wire from the horn ring TO ground (key on), the horn 'sounds', even when the horn ring isn't being pressed. question:

this means I hope some kind soul will run ANY kind of wire (old coathanger, piece of old baling wire, etc) momentarily from their horn ring to ground with key on, to SEE if THEIR horn blows then....

thanks :-) I still hope for an answer... :-\

Recall I measured the voltage on my ('71) horn half-ring; it was zero all the time.

'71 began the brass wiper strip under the horn button/ring. I didn't take this one apart, but I suspect yours has a separate wire for ground and for horn in the little harness that comes out of the turn signal assy. If they are reversed you could get a shock as the ring would be live from the horn relay (until ring pressed).

You'd have to autopsy the harness and identify each wire.

Speedy Jim

Speedy Jim wrote

ahh, yes, light bulb is =finally= going off above my head, as all you say 'rings true'(this _has_ been most mysterious>. will do as you've suggested, and thanks again much, speedy jim :-)

You're okay. That's exactly how it is supposed to work.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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This should measure 12V as long as the ignition is on, your horn is good, and you have a voltmeter with a reasonably high input impedance.

For some reason this whole horn thing is probably THE most confusing circuit in the whole car.

For 71-on:

The hot runs thru the horn and back up the column wiring to the leaf spring against the brass ring. There is a feedthru in the steering wheel connecting the brass ring to the horn ring.

The horn ring is suspended and insulated away from the steering wheel hub by bolts, springs and nylon washers.

The steering wheel hub is grounded via the steering shaft, jumper across the steering coupling, and, in some VW types, another jumper from the steering box to the pan.

When you push on the horn ring, it gets shorted to the grounded steering wheel hub, which completes the horn circuit, allowing current to flow thru the horn.

You can't get a shock from just 12V; it's just too low to feel except with your tongue. You can test this by putting your bare hands across any 12V battery. Even if you got your wristwatch between the horn ring and ground it wouldn't hurt you, because the current would be limited by the impedance of the horn.

The scheme on pre-71 cars is slightly different. In that case the horn ring is always grounded, but the steering shaft is "hot."

I prefer the early systems because the brass leaf springs against the brass rings always wear out on the late cars. Anyone got a good fix for that?

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Just to muddy the waters a bit more: The steering "shaft" is never hot. The shaft into the rubber coupling is grounded thru the jumper wire and the ball bearings in the gear box.

The steering "column" (outer tube) *is* hot (via the horn itself) on cars after the carbon brush/slip ring was dropped. (And I guess the column return was discontinued on cars with the combo turn/wiper switches.)

John Henry has an excellent series on horn schemes:

That said, I still don't fully understand how OP's car is wired:-)

Oh....the shock he gets isn't from the 12V, but rather the inductive kick from the horn relay coil when the circuit opens.

Speedy Jim

From: Speedy Jim ( snipped-for-privacy@nls.net)

well, that "autopsy" procedure I attempted yesterday (turned into kind of a daykiller). removed steering wheel, ign switch, and turn sig assy "almost completely", but left the wires hooked up. to compound the mystery: there are NO terminal numbers on rear (or anywhere) on the turn sig switch assembly, and the harness wire colors did NOT all match the colors scheme in bentley chart (suspect now that possibly the ignition switch has been replaced with a slightly newer one, but?). and the ign switch also has no viible terminal numbers on IT, either. also, at least one (apparently factory original) white wire wasn't even IN the chart, and the bentley chart showed THREE solid brown wires TO "the jumble" at the horn switch area, and I only have one = although, one or more 'shown as wires' MAY in fact be ground screws ). the bentley chart also does NOT "seperate" the wiring in that area by function: the horn wires, ign switch wires, hi/lo highbeams switch are all "jumbled in together" as an apparent single "unit" in the schematic... most confounding...

after spending the morning taking closeup digi-pics of the bentley manual wiring chart and 'editing out' some nearby unrelated wires, I was gonna print out a four page diagram "blowup" this morn of just the wires TO that "jumble area" and see, one by one, which color-matched my wires, which may've been replaced with "different colors", which may've been 'wrongly swapped' with other wires, and which, if any wires really WHERE missing entirely, and other stuff (it sure wasn't gonna be ANY fun...) ============================================================ ============================================================ From: Jim Adney ( snipped-for-privacy@vwtype3.org)

good, and you have a voltmeter with a reasonably high input impedance.

circuit in the whole car.

that's "putting it mildly" (see comments above :-)

spring against the brass ring. There is a feedthru in the steering wheel connecting the brass ring to the horn ring.

hub by bolts, springs and nylon washers.

across the steering coupling, and, in some VW types, another jumper from the steering box to the pan.

steering wheel hub, which completes the horn circuit, allowing current to flow thru the horn.

your text implies "the horn ring IS SUPPOSED TO BE "hot"; aka "the horn ring itself is normally hot" (when the key in on). OK, so good, then I'm OK :-)

how I got the shock was with back of my bare sweating legs (wearing short pants) resting on the aluminum door threshhold plate, then blowing the horn (admittedly, NOT something "ordinarily done" in the normal course of driving). ps-florida VERY hot & humid this time of year and my shop's NOT air-conditioned

thanks very much, jim :-)

============================================================ ============================================================ From: Speedy Jim ( snipped-for-privacy@nls.net)

inductive kick from the horn relay coil when the circuit opens. that MUST be it, and thanks again, Jim :-) ==================================================================== ==================================================================== From: Jim Adney ( snipped-for-privacy@vwtype3.org)

COOL! at this point I'm GLAD to hear that! THANKS again, Jim :-)

thinkin' about this was starting to "gnaw at my brain" a wee bit ...

and thanks again to ALL you guys - your help much appreciated

I'm really only familiar with the way it was done on type 3s, but I'd be surprised if the other types were any different. Prior to 71 here's how it was done on type3s, at least.

The hot went to the horn and then returned to the steering columm. Within the steering column this wire connected to the steering shaft bearing, which was isolated from the steering column by a nylon insulator ring. This made the steering shaft "hot," all the way down to the rubber coupling.

The horn ring was connected to a wire which ran down the inside of the hollow steering shaft and jumped the rubber coupler, grounding itself to the steering gearbox input shaft.

Thus the horn ring was always grounded, and when you push the horn ring against the wheel hub, which was hot along with the steering shaft, this provided a ground to the horn, which then sounded.

Did beetles and/or buses do it differently? Did buses use a horn relay?

That makes sense, but I didn't realize that they HAD a horn relay.

I gotta go check my Bentleys. ;-)

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Oh, yes, I see; you may be right. No horn relay on Buses.

Ghias had a horn relay cuz there were (2) horns. But I would expect to get some kind of shock with just the horn as the inductive load on other cars. Jim

Okay, I'll buy that. Everything would depend on your timing in relation to where the points were in the horn. If you broke the circuit at the wrong time you might get a shock. Inductive flyback on coils like this, where there is just the one coil so the "transformer" is just 1:1 generally gives you no more than a 2x voltage boost. I don't think most of us could feel that.

I know that 45V can feel pretty harsh. I just don't know where the threshold occurs; I thought it was above 30 V.

Note here that the proposed new car electrical standards run system voltages somewhere around 45V. Those will be MUCH less pleasant to work on.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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Sounds like Speedy Jim explained this. Must have been the inductive flyback of the horn solenoid itself. Interesting.

Hope it wasn't too bad a shock.

Back to your horn: It sounds like you've got it wired correctly. Does it work? If it doesn't, I find that the horns themselves are often bad by now. Many of them can be taken apart and cleaned up, but some are crimped together and must be replaced.

You can test the horn by just feeding it 12V directly, if you're not sure of your wiring. One way of doing this is to figure out which wire is the hot one bringing juice to the horn. Leave this one installed and simply connect a jumper from the other terminal to a known good ground somewhere.

----------------------------------------------- Jim Adney snipped-for-privacy@vwtype3.org Madison, WI 53711 USA

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it wasn't. someday I'll tell ya my "arc welding in the rain with semi-wet sneakers on" story....

yes, they both work fine, but getting any shock seemed 'kind of odd'. I was only really concerned that the shock 'indicated' there might be some possible add'l (unseen) wiring problem like frayed wires somewhere, or whatever...

thanks again to all :-)