Typically they are blue or yellow. I freely admit that I haven't installed every type of deck there is though. They are also usually labelled, so the color really isn't the primary source of...
it provides a signal to your subwoofer amplifier to turn it on and off with the car's key
try coloradofans.com it as everthing you could wanna know about colorados, it has helped me out sooo much
email adubitsky@lightcore.net
blue/white-remote yellow-battery red-accessory black-ground wh/blk-Lfrt gry/blk-Rfrt grn/blk-Lrear prp/blk-Rrear