I've got a 2003 BMW 330i (w/o navigation system). It's got the standard Harmon-Kardon "Business CD" stereo and is pre-wired for a CD changer. I believe I should be able to connect any A/V device to the wiring harness for the CD changer in the trunk.
But I have no idea which wire to connect to or where to get an adaptor that would let me connect a portable MP3/CD player (standard 1/8" headphone and "line out" jacks) to the harness.
Can anyone confirm that this is possible, where to get the right adaptor, and which wire I connect it to?