Retrofit 2017 SWC to 2014
 

Edit: This is now a DIY on retrofitting 2017+ steering wheels with SWC onto 2012-16 FR-S. This will probably work for pre-2016 BRZ as well.
You will need the replacement steering wheel, a wiring harness off a 2017 vehicle, AND a compatible airbag (they are all different shapes :( ), plus some type of SWC adapter if you have an aftermarket head unit installed. I initially tried using PAC SWI-RC. It talked (on setting 1, version 3) to the left side of GT86 SWC and my Alpine iLX-007, but it refused signals from the right side of the SWC. I returned it and bought Metra ASWC-1 instead.

[TO DO: UPDATE WITH PART NUMBERS; 2017 gt86 harness 81302CA360/81302CA160]

Note: the only reason you need a dash wiring harness is to scavenge some pins off them. It's possible to buy these pins at the dealer piecemeal, but it's way more expensive than to get a dash harness off a wrecked car on eBay - these can easily be found for under $100, closer to $50 if you're lucky.

So if you're installing a 2017+ steering wheel (doesn't matter whether it's GT86 or BRZ), here is how the two roll connector (aka clock spring) plugs interact. Disregard wire colors, yours may differ. Pin positions probably won't though, but use a continuity tester anyway to be sure. Note that the two plugs use slightly different pins from one another. I ordered spare pins from iwireservices.com, prepared with pigtails. [this space to be updated with final price for pins]

https://i.imgur.com/XzabmiS.jpg

[SPACE RESERVED FOR DIY WALKTHROUGH WHEN I GET AROUND TO PUTTING THIS TOGETHER]

Original post follows:
Stole this pic from another old thread. Anyone have an idea of what signal each of the wires in the blue tube carries? I know each corresponds to a SWC button on the GT86 wheel, I just don't know which ones. I plan to repin the other three wires (horn and cruise control) to an FR-S harness so I don't need to switch out my clock spring, then hook up the SWC wires to a PAC SWI-RC. Still gonna be expensive, as I will have to get a GT86 airbag, but no matter. The real trouble is, I don't know which wire does what and the electrical manuals do not help - wasted two hours trying to figure it out on my own. Thanks in advance, y'all.
https://c1.staticflickr.com/5/4168/3...847ba198_z.jpg

Basically, here's what I know so far re:GT86 steering wheel harness (top) and FR-S (bottom). Mad respect to anyone who can help me fill in the blanks, especially for the bottom one.
[edit: diagram omitted because it's misleading (no pun intended). Don't want it getting indexed by search engines]

I took on this endeavor as well. The steering wheel controls for the radio only have 3 wires - swc1, swc2, and a ground. I had to follow the wires to see where they go to, it took a while.

There should be 3 remaining wires/signals that pass through the terminal and goes straight over to the right side. Once they pass through the clockspring, the wiring heads up to the gauges (newer cars only). Once again, there was no easy way of figuring it out. I took some close up pictures of the SWC pcb with the traces them and mapped it out.

Which set of buttons do you have? There are many variations. I have full controls on the left side of the wheel, but on the right I have everything but the push to talk button.

edit: Also, if the wheel is from an AT car, there should be some wiring there for the paddles. Those wires should be easier to follow and rule out.

double edit: I forgot there is also wiring for illumination, 2 wires. All the buttons are lit, so it passes through the left set over to the right side of the wheel. If you have the physical buttons opened, you can see which wire traces go to the leds. I'll try to round up some info i found useful.

Thanks for the helpful response! Glad to hear it can be done. The steering wheel is from a TRD model, so definitely manual (as is my FR-S).

https://i.imgur.com/cUpWOaF.jpg

Also, I found a newer electrical manual. I think this is the relevant section, for anyone looking at this thread in the future. I guess there are only three wires to connect to my SWC adapter? Weird, I wonder what all the rest are for and why they go to SWC buttons...
https://i.imgur.com/ziyEJvO.jpg

Alright. Looking at the wheel i can tell that the wires in the blue sheath heading over to the right side of the wheel can be ignored (should be 3 wires). Those wires only control the gauge cluster screen.

That leaves 5 wires- 3 for your SWC and 2 for illumination. You don't NEED the illumination wires to be connected for it to work, but they won't light up if you don't connect them. I had to run brand new wires and tap into the radio harness illumination wires since there were no previous buttons to light up.

Your buttons are different than what I have, so the boards within are different as well. You will have to open the SWC and see what is what.

Here is an example of what I mean.

https://i.imgur.com/bmtAatf.jpg
https://i.imgur.com/JyydCIs.jpg

This thread was helpful.

http://www.ft86club.com/forums/showthread.php?t=120646

Thank you so much, you've been immensely helpful. When I finish this, I will make this thread into a very easy DIY for anyone else who wants to do this.

No problem, good luck! :thumbsup:

Hoping to take on this retrofit in my 2013 this winter as well. Just working on gathering all the things I may need. I have already done the 2017 gauge cluster upgrade. Looking forward to seeing how it works out for you! And hoping you'll have the easy DIY done by the time I get to it cause all this electrical stuff makes my brain hurt! lol

I have the last of it arriving tomorrow, but I probably won't have a chance to actually work on it until next weekend. I'm still gonna solder together all I can (as far as what's possible to do outside the car) before then and take pic.

How have you made out with this process?

Retrofit 2017 SWC to 2014
 

I am taking on this project with my 2015 BRZ, so far I’ve ordered both a used 2017 wheel, and 2017 airbag. I was thinking I might need to get a 2017 clock spring but I’m starting to wonder if the current clock spring will work.

It seems to have the right amount of pins, although I’ll have to do some continuity checks to ensure they’re all active.