Maybe your right. But how can I recognize where the I-bus signal is fitted on.

The retrofitcable of kufatech doesn't have (?) a connection like 12 pins (this is what the forum bimmerboard says). All connections are full, except the one in the front (where the original plug is for a radio, and on that plug i can fit my complete cable.)

This is an image of the cable i have, maybe it says you something