Its not displaying but it on the screen is black but on

Hi,

The LCD screen flex cable connection to the motherboard may be loose or the LCD screen may have failed. Either way the tablet needs to be opened to ascertain the problem.

Here is a link to the ifixit guide(s) Samsung Galaxy GT-P5200 to repair your tablet. They are useful in that they show how to disassemble the tablet to gain access to the LCD screen and its' connection to the motherboard.

Here is a link to a supplier of the parts for your tablet. It is not a recommendation to use them, it is shown to give an idea of the cost of the part. There are other suppliers that may suit you better. Just search online.

Hopefully this is of some help.