2009 528i

need to add an aftermarket amp/sub to this car. the output to the rear and door spkrs appears to be crossed over ( no good for the amp source for bass ). this car doesn't have the subs under the seats. any one know where to pickup the signal for the new amp?

It has been a while since you posted. Hopefully you have found your answer but I will share my wisdom in case it helps. The amp should be located in the trunk on the driver's side under the side panel. There should be a left and right sub output regardless of whether you have a subwoofer or not. I can not seem to find the wire colors, but those are the only outputs from the amp that will work. I know it is available through a google search, but I cant seem to find it now. Hope that helps a little. Sorry for the late reply!To master and control electricity is perfection. *evil laugh*

thanks, i did fix my dilema, i took my signal from the line outs at the deck, PS there were subs under the seats.