VX SS BCM wiring issue.

[Damo33]

Been working on a VX SS lately came in doing doing weird electrical freak out with ignition on all really would drop out clicking, fuel pump drops out, does it running also randomly, kept pressing lock unlock and it came good. Disconnected battery for week or two when I reconnected battery I notice no unlock / lock, no security light flashing, no interior light, no power windows, no fuel pump. Found there was no power too OBD2 plus at pin 16 orange / black trace. supplied ignition + and I got power windows and fuel pump but still none of the above. Supplied batt + and got everything back working, locking, starting, running ect. even swapped out BCM but still lost power down pin 16? wondering if anyone else has came across this issue. fuse 31 is fine, other fuses seem fine.

Thanks Damo