Help: installing carbon contact pin to restore horn with Momo steering wheel

[n3985]

Bought my E36 with a Momo hub and steering wheel installed with no functioning horns (horns removed).

After a couple close calls on the road I need my horns back

I removed the Momo wheel and hub, bought the OEM carbon contact pin but lost as how to make it work.

Here is the pin:



Here is where it goes:



And here is where I am missing two connectors from OEM slip ring, I think one of these contain the horn + and - wires.



I Googled and found a few threads on how to install non-OEM wheels but honestly a bit lost and/or can't comprehend the steps.

Help? Thank you!

[n3985]

bump....no one? I found DIYs for reusing the OEM slip ring but also OEM wheel. Still can't find a solid DIY for aftermarket steering wheel and retaining horns.

[berny2435]

I've haven't replaced my wheel yet but see if you can find what you need here.
http://www.pelicanparts.com/bmw/tech...ring-Wheel.htm
http://www.pelicanparts.com/bmw/tech...r_Bag_Lamp.htm

[propcar]

bump....no one? I found DIYs for reusing the OEM slip ring but also OEM wheel. Still can't find a solid DIY for aftermarket steering wheel and retaining horns.

I'm on this same boat...

I believe the brown and blue wire is the one for the horn... assuming one is ground and the other is +


I removed a 3-spoke US OEM steering wheel and my OEM slip ring did not fit on the back of my Nardi Hub. That's my problem, however I've heard the 3-spoke slip ring is smaller than most normal E36 M3 4-spoke slip rings. Sort of backs up how mine didn't fit, the Nardi hub, the slip ring is too small to reach the 3 bolt hols on the hub.

So ideally, I'd love to get a hold of 4-spoke to try it out.

If not then I'll get the carbon pin and this slip ring, which I read should work with the carbon pin.
http://www.ecstuning.com/Search/Site..._Ring/ES53170/

Also, my turn signal 'auto cancel' when you turn doesn't work anymore, so I have to manually return the turn signal to center... I believe the OEM slip ring will be needed to retain this functionality as I think that black tab hits a switch when you turn in order to 'cancel the turn signal'.

[n3985]

OK maybe I was missing information, I need the OEM slip ring AND the Momo/other brand hub adapter to make the horns work?

[propcar]

I don't think it's the ONLY method of wiring up the horn... but it's the one closest to how the wiring and stock functions were designed :P

Although, we're not using an airbag so there goes half the function of the stock steering wheel and half the function of the slip ring

[n3985]

Update to this post, found the solution in this thread and will work for all universal steering wheel hubs such as Momo, Sparco, OMP, NRG, etc.

http://www.bimmerforums.com/forum/sh...-Wheel-Install

You need to cut off the connector to the carbon pin or use a wire splice.



Then add more wiring to lengthen as needed



Insert the carbon pin



May need to hammer it in, a deep 13mm socket works wel



Inside the horn plug, the left pin or brown/red wire is +12V. When you press the horn button, it grounds this switched (to ignition) +12V.




The carbon pin touches the back of the Momo hub's copper ring seen below



Next step to connect the red/brown wire to the carbon pin. You can solder or splice.

*stole this pic off vwvortexx*

You can see below the BLACK wire connects to the copper ring and the YELLOW wire will function as ground.



More details from Momo



Lastly when installing the horn button, make sure the BLACK wire connects to the center and the YELLOW wire is ground.



Hope this helps anyone confused in the future!

[propcar]

I bought both the carbon pin and the OEM slip ring with the copper contact ring.

So when I test the horn and the wheel isn't fully bolted up, I touch the metal of the piece that surrounds the horn and I touch the metal part of the steering wheel and hit the horn it sounds. But when I screw down the steering wheel tightly to the hub then it doesn't work anymore.

The wire that goes to the horn is the power and I don't have a second wire... so the metal at which the horn is touching, (it has a prong on the horn that touches that) is I'm assuming the ground, but I guess it's somehow not really grounding correctly when it is bolted in. It's really silly but I'm not sure how to fix it! I only have one wire that goes to the one spade connector on the horn.

like this one

[TXBDan]

The spring on the side of the button is the ground contact. Make sure it has a ground path to the wheel and through the hub. I'm running a couple wheel spacers and had to sand the paint off to get electrical contact through the interfaces.

[propcar]

yeah I figured that's what it's for, my horn is inserted into this horn retainer (pictured) and of course once it's all bolted down the horn simply doesn't move anymore. I also have a ring that's part of the steering wheel that goes after the horn retainer and is the final piece of the assembly that holds the wheel + retainer into the hub.

It's bolted in this order (screws) > (black aluminum ring with holes) > (horn retainer with horn inserted) > (steering wheel) > (hub) > (slipring)

[n3985]

If you have the aftermarket hub do you really need to use an OEM slip ring? I ask since the way the OEM setup is designed vs. aftermarket hub, the polarity is reversed. I think what is going on is the OEM setup, when you press the horn it provides +12V. Whereas in the aftermarket setup that I went to through, pressing the horn provides the ground. So when using both, the + and - are not matching correctly between your OEM slip ring and aftermarket hub.

[propcar]

yes I have to use the slip ring with the contact, because the nardi hub doesn't provide the tab to kill the turn signal and the hub doesn't have the contact for the pin either... to add, I'm not using the OEM E36 M3 slip ring as I had a 3-spoke wheel, I bought a slip ring from like an e34 or something like that with the contact track to work with the pin.

[n3985]

Perhaps try using a Momo or Sparco hub would be easier then? The steering wheels all use same pattern and can use each other companies' hubs, quick releases, and etc.

[propcar]

Nardi pattern is different, I believe. I don't think it's really the hub, I think it's a grounding problem... not sure if maybe I need to add a ground wire to the ground 'spring' on the side of the horn button, to ensure it does remain grounded even when it gets bolted down.

[Crustashio]

I'm going to bump this thread because I am having the exact same issue - horn stops working as soon as I tighten the wheel bolt.

Using a momo #2008 hub, OEM carbon pin and sparco horn button. Horn works fine when the hub is on the splines, but if I tighten the bolt it stops working. It's got me stumped.

[propcar]

I'm going to bump this thread because I am having the exact same issue - horn stops working as soon as I tighten the wheel bolt.

Using a momo #2008 hub, OEM carbon pin and sparco horn button. Horn works fine when the hub is on the splines, but if I tighten the bolt it stops working. It's got me stumped.

I had to run a seperate ground wire for the horn. I tied the wire around one of the metal pieces on the adapter. Fixed the issue entirely. I'm using Nardi but probably the same issue/fix.

[Crustashio]

You have a slipring, right? I can't provide a separate ground to the hub with the momo setup without just having a loose wire wrap around it.

https://www.turnermotorsport.com/p-1...6-3-series-z3/

That's what I'm using. I even made sure to read a ton of threads before I bought the hub (because I need horn for safety inspection). I'm going to go back tonight and dig out the multimeter again to triplecheck it all.

edit: from further googling it seems to be a common issue that the shaft and/or column isn't grounded properly.

[propcar]

I have the carbon pin 'slip ring' from an E34 or something like that... I forget what model. While this did provide somewhat of a ground, it wasn't a good enough ground when the steering wheel was bolted together (seems to be the results of your search as well), so the horn would work intermittently. Once I ran a separate ground wire and just wrapped around the nardi hub adapter, horn has been working great.

[Crustashio]

Well, I finally fixed the problem...by accident. I went back to the stock steering rack for autoX classing and accidently discovered the horn works now because it started going off while I was driving around town this afternoon. I had tucked the wires in the hub and they must have started touching. I reconnected them to the horn button and it's fine. I'm not about to reinstall the Z3 rack to confirm it, but either the stock rack or having the steering coupler off and on again fixed the column ground.