Know it's an old thread but did anyone get to the bottom of this? It just happened to me, phone was working fine after battery replacement for a few hours but then when it was time to charge it again the screen stopped working after a while. I opened it back up and the screen kept coming back on and off for a while until next day it's completely dead. Phone still turns on but can't see anything. I did yank the battery pretty hard to get it off and didn't clean all the glue when placing new battery. I also used plenty of alcohol so maybe that damaged it? In any case does anyone know if replacing the screen fixes the issue or is it a bigger problem?