| I've just finished wiring in a CD player to mine (saving £30 by making up my own lead) so got all the Blaupunkct connector schematics off the net. Have you actually tried pressing the CD changer input select button (top rhs on my radio) with the MP3 player running? If that doesn't work then as you obviously suspect the radio may need a signal to tell it something is connected.
I presume you are referring to the C3 connector (rhs of the 3 looking at the back of the radio)? If so you should have the following (from the top)
Row 1 = 13, 16, 19
Row 2 = 15, 18
Row 3 = 14, 17, 20
13= Bus in
14= Bus out
17= Bus Ground
15= +12V perm
16= Switched +12V
18= AF-Ground
19= Line in Left
20 = Line in Right
I assume your connector is wired to 18, 19, 20? Maybe you need to loop +12V (ie pin 15) to pin 13 (ie Bus in) so the player knows something is connected? That would obviously be risky though if its expecting a 5V digital signal :-( Might be best then to check the volts on "bus out" from the radio that should give a clue. If its 5V then you could try looping "Bus in" and "Bus out"?
This input to the radio is definately used by some hands-free sets so you could try searching for info on those as it might help. Other than that you could try searching the rover MG forum as they mostly have Balupunkt radios fitted and they have a specific audio section for posts.
Good luck,
Keith  | 
Linear Mode
