What kind of phone was your original system?...

I just noticed that you are in the UK. This could add a complexity. In the US market, we got fewer phone choices; therefore all of the pre-wiring is the same and compatible with the TCU modules. In European markets, BMW offered more phone systems, and some had different wiring. It gets tricky, because some of these other systems have the same 54-pin plug, but the wiring is not the same-- search the posts on the BIT II system, for example.

__________________
SOLD
2000 E38 750iL Highline Edition, Upgraded with the lastest 2006 X5 Electronics
MKIV Navigation, 16:9 Display, Bluetooth, TV/Video with Backup Camera, Sirius, and Aux Input