Wire for aux jack

I have a pigtail connector for a 2006-09 Prius to wire in an aux jack from the center console to my aftermarket radio. I'm hoping someone knows what color corresponds to what portion of the audio so I can wire in a 1/8" stereo plug. Hopefully I'm making sense.

I can take a picture of the pigtail, but it has 4 wires. I'm guessing it's ground (bare wire), right (red), left (green), and common (white). Is there a site somewhere that shows what each wire is for?