Black screen on the monitor after 2 seconds! [Closed]


I have a problem with my 19" monitor. When i plug the monitor on, it shows light 2 seconds and then goes black. If i press the button off and press on again it shows light 2 seconds and everything is ok, then black screen again. I can do this 1000 times and nothing will change.
The problem is not in the computer but in the monitor for sure.

First i tried to replace capacitors. I replaced all the capacitors on the board but nothing changed. Then I replaced the backlight and still the same problem - 2 seconds work after that the screen is black. Now i have no idea what could it be. I tried everything with the settings on the monitor but i had no succes.

Do you know what could it be? The backlight and the capacitors are new so what is the problem?