We completely dissected our docking connector's wiring in order to successfully install the Empeg into my VW Jetta. It's using all 16 pins, as follows (note that I don't know which signals are carried on which wires in the serial cable):
1: +12V (and +12V line on serial cable) 2: Serial Yellow Wire 3: Rear Output Right 4: Rear Output Ground 5: Rear Output Left 6: Aux Input Right 7: Accessory Power Out / Serial Blue Wire 8: Antenna 9: GND 10: Serial Red Wire 11: Front Output Right 12: Front Output Ground 13: Front Output Left 14: Aux Input Left 15: Aux Input Ground 16: Antenna Ground
Lots of different grounds - but they're all necessary, as I'm sure someone
from Empeg will tell you as well...