after successfully open the iPhone .you might be so excited .and be less careful while removing the plug .the wrong way to removing and connecting the plug & connector would easily got the screen damaged .or furthermore ,got logic board connector damaged ! if logic board connector got damaged ,even you have new screen .you already can do nothing with your iPhone .

when removing the connector ,do not use "hand" to pull them ! instead ,Use the flat end of a spudger, or a fingernail, to disconnect the digitizer cable by prying it straight up from its socket on the logic board.

and most importantly .When reconnecting the cabledo not press the center of the connector. if the position is correct ,you don't need too much force .Press one end of the connector, then press the opposite end. Pressing in the center of the connector can bend the
component and cause damage.