I have a 2004 X5 with 84116947308 TCU which only has assist. I picked up a 8411694693 which has assist and Bluetooth. I switched the units over but nothing! I tried to pair it never displays anything about pairing or lack thereof on the display.

I have tried the pair in the first 2 minutes, holding down the shouting man button - everything I have read on any forum about BT. So is there soemthing else I need apart from jsut swapping the unit? or caoudl soemthing else be not working?

Thanks!