HU cannot detect CD changer (original parts)
horribly designed and will (will) continue to exhibit problems. the only thing I
can think of is to try a reboot, that is, disconnecting battery and allow electrics
and electronics to wake up again after reconnecting.
i've read where it may sometimes take a few mins of power down, to even an
overnight down time.
BE SURE you have your radio code on hand, otherwise you won't be able to
unlock the head unit after reboot. this is part of the anti-theft feature.
http://www.benzworld.org/forums/w210...air-guide.html
I think the best solution for music is to install a AUX-IN cable on the radio and use an MP3 player.







