mobile

Hello,

after the touchscreen of my Sony Xperia Z broke down, i decided to repair it by myself with an old Sony Xperia Z, which was damaged by water. So I took the battery and mainboard of the phone with the broken touchscreen and put it in the phone with the water damage. All worked fine, and the phone is working, except for the power button. If I press the button only for a moment, the phone goes to sleep, but the screen pops up again a few seconds after. Sometimes also the shutting down menu pops up.

So my question is if there is a way to repair that by myself (maybe I damaged a cable), or if I should go to a repair shop?

Thanks for answers.

P.S. Sorry for my english, I am a non native speaker.