I have a moto x pure edition, and the screen won't power on ! Please help!

[alefy afonso]

Hey, I have a Moto X pure edition. I did the screen replacement for the second time. The first time everything worked great , and now the second time I do it ... well I have problems. So the phone does not power on. I checked the connections and everything is connected correctly. Now when I connect the phone to the charger the screen lights up and goes away, then when I "Hard Reset" the boot-up screen comes up.. please help ! What could it be?