I found this a while ago in these forums it is the only thing I could find, I bought new speakers and a sub that I have had for at least 6 months and I am ging to install them very soon so I am re reviewing my notes from looking this stuff up a while ago. I have a 2013 SEL.
Car Radio Battery Constant 12v+ Wire: White/Red #02 Car Radio Accessory Switched 12v+ Wire: Blue (remote-out) Car Radio Ground Wire: Black/Blue Car Stereo Antenna Trigger: Yellow/Green Car Stereo Amp Trigger Wire: Purple/Red --- #08 Left Front Speaker Positive Wire (+): White #21 Left Front Speaker Negative Wire (-): White/Brown --- #11 Right Front Speaker Positive Wire (+): White/Purple #12 Right Front Speaker Negative Wire (-): White/Orange --- #09 Left Rear Speaker Positive Wire (+): White/Green #22 Left Rear Speaker Negative Wire (-): Brown/Yellow --- #10 Right Rear Speaker Positive Wire (+): Brown/White #23 Right Rear Speaker Negative Wire (-): Brown/Blue