Thanks top for the prompt response. What I did is I ran the front pdc through the firewall as you had in one of ur posts and connected one end to the pdc unit in the trunk. The thing that threw me off and the instructions weren't clear to me atleast on how to route the wiring harness with sensor part out of the Ecu box so I can close the box.
I hope I m making sense
09 e92 335i xDrive/Black Metallic Sapphire/Black Dakota Leather/Steptronic/Cold Weather Package/Premium Package/Sport Package/Xenon/I-Drive/Front&Rear PDC/Alarm/HIFI/Electric Rear Sunblind