Any one have a link or diagram of the BUS system on the 2007 X5?

I know that it will vary some depending on the features you have. But just a general flow.

I just find it odd that with the Optic cable not connected the iDrive works fine but connected its dead?

Only issues that I have had that would be related to the iDrive would be the damn SOS message and the fact the X5 is coded for BT but the link cant be found?

thanks