Are you talking about a black plug (known in manual as E62 or E63 - a note for me!) ? This is a large plug with 47 wires!
On E62 (with VDC) or E63 (no VDC):
Pin 1 - Blue - CAN-H signal
Pin 2 - Pink - CAN-L signal
Pin 16 and 47 are ground (connected to E59 on the firewall - called E60 in non-VDC vehicles).
It's proving quite difficult to haul the rest of the pin information out of the manual. I can do it, if the info is actually there, but I think my 2011-2014 Navara workshop manual is missing BRC.PDF (Brake Control System) so I only have the master wiring and harness diagrams.
What specifically are you after, and have I got the correct plug?