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I left my iphone sittimg for a week with no screen put the new screen on and it wont turn on i forgot to unplug the battery but it is recognized by the computer when plugged into it but wont charge or turn on and i lost all the screws to the cables metal plate for the lcd but ice done it before but still
Sounds like backlight filter blown when plugging the LCD with the battery still connected to the board. Could even be just a bad screen even. If it’s recognized by the computer check it on iTunes if it says trust this device or locked with a passcode you know the iPhone has booted up successfully.
Is the battery connected correctly? Try checking if the cables are in place since it could easily be a loose cable if nothing comes up on the screen.
