No - a TCU module in a x5 could have the power on pin 1 and ground on pin 2

a tcu module on an x3 could have ground on pin 1 and power on pin 2

If you are saying the wiring for TCU modules are identical then i understand what i need to do, and as long as i look at ECE diagram in WDS and rewire to match that, i can get any ECE TCU module and plug it straight in.

I'm now looking for one of these (sourced form here http://www.bimmerboard.com/members/p...artNumbers.pdf)

European GSM based TCUs - won't work in US

TELEMATICS CONTROL UNIT GSM Jan-05 84116946991
TELEMATICS CONTROL UNIT GSM Mar-05 84106965055
TELEMATICS CONTROL UNIT GSM Sep-05 84106964113
TELEMATICS CONTROL UNIT GSM Jul-06 84106963758
TELEMATICS CONTROL UNIT GSM Nov-06 84109129850
TELEMATICS CONTROL UNIT GSM Mar-07 84109127894
TELEMATICS CONTROL UNIT GSM 84116946011
TELEMATICS CONTROL UNIT RFMD GSM 84106978533
TELEMATICS CONTROL UNIT GSM Jul-06 84106963758

TELEMATICS CONTROL UNIT GSM Nov-06 84109129850