The question I have for you guys is what are you trying to achieve? I have been slowly trying to figure out a way to tap the wires to add a subwoofer and an aftermarket amp. I was actually going to tap into the wires that go directly to the factory amp. After looking at this
thread and bmwtips.com, figured that white wire to be the remote. I still have not gotten a chance to figure out + and -. All I need is 2 wires and I would get a converter to change speaker wire to RCA. That way I could put an aftermarket amp. I actually took the Nokia box apart. Here are two pictures. The question I have is whether you can tell which color (green or green/black) is + or -. Maybe you guys can look closely at the picture of the speaker and figure it out. The right prong is larger than the left but doesn't have a marking for + or -. However the black/green wire corresponds to the larger prong while the smaller prong is the green wire.