check this thread on the connection of the trigger wire and the selection of the relays. The realya is about $3-$5 from a local Radio shack. Let me know if you have any questions.

http://www.xoutpost.com/bmw-sav-foru...ew-camera.html

Does your car have factory PDC?

__________________
E53 X5 4.6iS
147K mi - Sold May 2013
Tireprints left in:
USA, Nicaragua, Costa Rica, Panama, Russia

E53 X5 4.8iS built 2005-10-17
66200 mi - June 2012
96000 mi - June 2013
112000 mi - June 2014
OEM fire extinguisher
OE first aid kit
OE tow hitch
OE TV module
OE aspheric mirror
K&N air filter
black/white badges
rear camera
4-channel video recorder

Here is the list of things I have done to the X