Need some help.

Just been out to my mini and it wont start. Thought maybe due to a dead battery. Put on charge and it is reading full battery. When I mean it wont start I mean that even when you put the key in it doesn't light up. Dash etc, It's like it is dead with no power. Checked for lose cables etc but everything on the battery etc seems ok. This has never happened before so I'm not sure on what it could be.

Any advise .... pretty please

All sorted now. It was the battery. The charger is had it. Read fully charged but must be empty. I jumped started it with my old mans disco and it was fine. So just a flat battery.

Chaos avoided.