X5 has totally lost power

[bigshout]

My wife has gone to use our X5 today but found that the car has lost all power, the doors won't open from the key, engine won't turn over and lights won't even come on. It seems weird that the car battery could lose its charge so quickly, the car has shown no signs of a weak battery and the car has turned over first time every time since we have had it. The car was last used around 6pm yesterday. I know the lights couldn't have been left on as they come on automatically and the car was locked. My wife also noticed her Bluetooth phone kept on connecting and disconnecting from the car last night and this morning even though the car wasn't in use. It seems to be a weird one and I don't know what to look into first.

Any help in identifying why the car could have drained the battery would be appreciated.

[Sanj]

Check the connections of the cables to the battery first. They could have come lose, mine did....