iPhone 5 dead after Screen replacement

Hey,

my iPhone 5 is dead, it cant get powered on and wont charge. I tried different cables, Recovery and DFU and the reset with the Sleep- and Homebutton.

Okay, but whats happen... The screen of my brothers iPhone showed some lines an he came to me for advice. We chanced our screen to check if the problem was thedisplay or the Phone by itself. My Display worked fine in his device and his display show the lines in my iPhone. Because he left the country for a few weeks i gave him my display.

At this point my phone worked well but it showed the annoying lines, because i use my iPhone like a pensioner i used take the phone from my company as my primary device. The defective iPhone was around 4 Months in a drawer until i decided to repair it. Yesterday the spare parts arrived (new Display and Battery) but the phone wont turn on. I tried it with the defective Display and the new one. I checked the connections of the flat cables approximately 15 Times and rebuild both displays twice.

- iTunes did not recognize the Phone

- it do not vibrate when the wall charger is connected (tried to charge it for hours)

Did somebody have some advice?