Originally Posted by mellephants
Here's the steering wheel control adapter. Just make sure your aftermarket HU works with this kind of device.
Axxess Metra ASWC-1 $55.00 http://www.amazon.com/gp/product/B00B4PJC9K
Otherwise use the PAC SWI-X. That will work with any HU that has an infrared remote controller. I've got a used one I could sell you, if you go that route, since I'm switching to the ASWC-1.
I'd already ordered the ASWC-1 when you posted your reply. I just now had the time to install it, and I can't get it to work. I followed the instructions for the 2012 Focus, but all it does is turn the volume all the way up and disable the touch screen on my Sony head unit. The lights flash like they're supposed to, but the steering wheel buttons aren't working at all. Have you had any luck with yours?