Mecer z140c edu not turning on

I have tried several ways to turn it on but it only shows the Mecer logo and automatically switched off again, when plugged in charger, it's turns on and off only displaying the Mecer logo. I've tried to hold the power button for 30 seconds, Ctrl +Alt+Delete, ESC, F12. Please help what could be the problem, the battery is working perfectly fine. I documents that I can't afford to lose in this pc.