It looks like the sat nav system is the culprit of my battery drain (every 24hrs or less)
I pulled/disconnected the DVD gps nav system (where the sat nav disc is) from the boot/rear of the X5 on Saturday, returned to the vehicle 24hrs later and it started no problem battery is alway dead after 24hrs lay up.

I need to know if there is some type of relay or whatever that controls the power from the MID on the dash to the unit at the rear of vehicle which might be faulty?
ie: not switching off power when the ignition is off (vehicle not in use) or can I put a relay switch or something between the MID at the front and the Dvd gps disc drive at the rear

PS
This could be the cause of other BMW vehicles battery drain, according to what I have read the power to the gps unit (where sat nav disc is) is meant to switch off after 1 minute