Ipod won't turn on after replacement

Ok. So I will try again 🙂 my ipod won't turn on after a replacement. The screen is black. I have tried two other LCD's but the screen is still black. Itunes seems to reconize my ipod and i haven't lost anything yet. It can charge too. The only thing seems to be broken is the wifi antenna , copper tape and the power button. What could be the problem? Is only the screen who wont turn on , but the ipod still works.