Help needed: with Sparco wheel, how to wire horn?

[jareds941]

Hi all-

I've got an NRG short hub and quick release to go along with my Sparco wheel as I build out my 2004 M3 track car. I feel like I've searched the Google and the YouTube but with no success on understanding how to go from the pins on the female side of the plug in the column (OEM has a female connector that simply plugs in) to the 2 wires I need to make the horn work.

Has anyone done this before, and maybe have some pics? Or even just a clear description? I'm competent with wiring stuff, but it doesn't come naturally so any "descriptions for Dummies" would be majorly appreciated.

For reference, here are pics of the car side, quick release wiring and also the connectors that came from NRG.

[MarcoPolo]

not sure if this will help but 2 of the pins are needed for the horn to function. if you look at the OEM harness, the black is most likely ground and the 2nd one i don't know but i'll look it up. what i ended up using was the very small square connectors that are used to wire up CPU's on motherboards. sorry i cant' be more descriptive. i went to a computer repair shop and he just gave it to me. it was perfect. i crimped the other end and just tapped it into the horn.

you could look at pluggin the OEM wire in and just use a wire tap to grab the proper 2 wires.

edit: correction..brown is component ground. i misspoke when saying black.

[MarcoPolo]

the below are the type of connector i'm talking about. i plugged 2 of those in and on the other end you can crimp the proper connector that you need.


also, googling says that the Violet and Brown wire are what trigger the horn...you're OEM wiring harness should tell you which ones those are....hope this helps.

[jareds941]

Thanks for the help MarcoPolo. I have a pic of the OEM plugs from the wheel (which I've since sold) but there are lots of wires running into the 2 plugs and I can't be sure of what is what from the pic (wasn't thinking I'd ever need that info 🤦♂️). If I could find the pin out diagram and then identify which one pin was horn and which was ground, I'd be set.

How did you figure out what pin on the car side to plug them in to?

[MarcoPolo]

Those 2 pins. Those are pins 5 and 6.

[jareds941]

Amazing!! Thank you I’ll try it out! 🙏

[Pnick]

Brown wire is the designated component ground...at least for the e46. The only black ground that I'm aware of is the battery ground.