I seem to be missing a wire of some sort or a connection. With the wheel mounted I can't make any connection. Here is what is under the wheel in my 71. Am I missing something or am I just not making a good connection between the ring and the electrical pick up?

Do you have the horn plunger in the steering wheel?

I have this.Click to view attachment
And thisClick to view attachment

Looks like you have an early car and a late wheel.

The Cap'n

Definitely a late horn pad.

Might need to do a wheel swap. See the parts diagram at pelican parts it's a spring loaded plunger that goes through a hole in the wheel and contacts the metal plate under the wheel.

How can a late wheel fit? I thought that they were incompatible and required different hubs to mount an aftermarket wheel?
Can I just get a Momo with a horn button and be done?
is 914-347-832-01-OEM, the "73mm horn contact button" what I need?

I don't have a horn contact button that you need but I have the other parts to make your horn work. Free + shipping. Looking closer at the pics, you have the correct early wheel and early hub. You just need the parts from an early horn pad, the one you have Is for the later wheel that uses a wire instead of the horn contact pin.

Yes.

Looks Like I will be placing an order Monday. I should probably make a list to save on shipping and time. Sounds like an excuse to spend Sunday afternoon browsing for other things to add on....

So it looks like I need an early horn pad.
Is there a way to make my late pad work by modifying it?
I assume that this is NLA from Porsche, any vendor jumped on this bandwagon?
Would this get me what I need? http://www.914world.com/bbs2/index.php?showtopic=244526
Do I still need a horn plunger with that wheel?
Sorry to he so helpless on this, but since I don't have the parts I need, I can't look at them to see how they work and figure out a way to make mine work.
Do I need a metal contact in my late button to make the early plunger work? Could that be made?
Will these work with my pad?
http://www.914world.com/bbs2/index.php?showtopic=243399
I am mostly questions at this point. Thanks for supplying answers!

Looks like Mepstein has me covered.
THANKS!

Received the new pad from Mepstein and I am not sure what difference it should make, the only difference appears to be that it has no capacity to attach a wire.
Swapped it in.
Picked up the plunger from Zims here in town.
Assembled it with no luck.
Picture shows the two plates.Click to view attachment

The top of the horn plunger runs against the flat metal bracket instead of using a wire to make the connection to the tab on the plate.

It does not touch the bracket. It pokes into the center, where there is a hole.
Is that plate supposed to be grounded in some way so that when the plunger contacts it the circuit is completed?
The parts diagram on Pelican is too small/lacks the detail to help me out.

It should go in the hole on the right hand side of the hub, not the center. It's the only hole on the metal bracket on the face of the hub.

The bottom of the horn plunger will run against the metal disc on the steering column. As shown in your first pic

That explains much! Thanks the exploded parts view just showed everything exploded.
I will try to sneak by and try that tomorrow!

I got the plunger in today and that makes much more sense, but still no honking. So I pulled off the pad, pulled off the wheel and looked for current. I thought that the ring was hot when I checked this before, but now it all seems dead.
My next step is to pull out the Haynes and start tracing the wire back.
Do I understand correctly that on the 71' there is no relay but the horn ring is really hot and in the circuit to the horns?
Any suggestion for common places to look for a fault?
All my fuses look good in the dash and also in the engine bay.
gratuitous picture of correctly installed plunger.Click to view attachment

maybe try shorting the horn to make sure it works.

Don't I need to pull the bumper to get at horns? If there is no power at the wheel, that would seem to be a bigger problem. I can go either direction on this one. I thought that it might be easier to start at the source, rather than the destination.

can you short it at the steering wheel?

I can't find anything hot at the steering wheel to short. The contact ring under the wheel should be hot correct?

So I pulled the bumper and the wheel. I managed to get 12 volts at the contact ring. It looks like I have one reluctant horn and one dead horn. I also don't seem to have enough juice to run my air-horns. I will pursue this more at a later date. I also discovered a variety of issues with the fog lights. Fixed some things that appeared to be problems, but they also are not working right. Oh the fun of 40 year old electrics! I have found a couple of wires just dangling free under the dash. I fear I need to pull it and find out what is left loose.

Is there a bottom to this hole?

are there two horn button plungers? It looks like mine is too short and it is part number 914 34783100.

correct part# for. what is the wheel part number on the face of the center? iirc you still need the wire for the ground as the plunger completes the circuit. swapping early to late can require the cup on the rear of the wheel changed accordingly.

wheel is part number 914 34780510. The plunger fits and should be making contact but is not long enough to reach the ring. Am I missing a part or do I have the wrong plunger?

Plunger needs to be about 3" long. Not the 1" version that 911's use.

I can confirm that. I lengthened my plunger and it honked my new horns.
Back to Zims I go!
During the process I found two live, unconnected wires loose under my dash, and I need to find out why I am not getting power to my foglights. Neither the brown nor the grey wire that are loose appear to be related to the forglight switch, but that is another story. I figured I would take a look at those since I had the bumper off.

Bad relay for the fog lights found. Correct part coming for the horn.
Hopefully those are both done and done!