Chosen Solution
I changed the screen on a iPhone 6s, when I was to power on the device there was no apple boot logo. I know the phone is on because of the sound it makes when I connect to the charger, and it is recognised by my computer, sometimes the lcd flashes on for one second then goes dark. the touch works as well since I can unlock the phone and hear the buttons being pressed on for the passcode. This problem now happens with the old screen as well and also with other new screens.
Sounds to me like you’ve broken the LCD socket on the logic board. This requires microsoldering, if you have the tools https://www.google.com/aclk?sa=L&ai=DChc… Stjin’s right. Maybe you can just clean it with 90% isopropyl alcohol
Hey hejokr13, I think the connector on the logic board of the phone is damaged or it’s a bit dirty. You probably have to replace the logic board.
