Plug [Q] EKEN T10 Tab not powering on if not connected ?

Hello,

Here is my problem,
I have an EKEN T10 10" Tablet on the Original ROM,
It has suffered some fails and showers,
and been turned off for some months,

Now it Doesn't turn on if it is not connected,
I just have to keep it connected to pass the android logo,
then I can disconnect it from the charger,
And,
Every time I turn it on, it is on 01:00 01 January 2010 !

Any ideas are welcome !