Chosen Solution
So I installed the screen tested it before assembly which worked but when i put it back together the screen was on but only black.
Have you tried holding the home and power buttons down at the same time for roughly 10 seconds? Have you checked the cable connections to see if they are seated properly?
Try disconnecting the battery, while it is disconnected re-seat all of the screen connections so you know they are in all the way. Then hook up the battery and turn the phone on. It should work If it worked during testing and now it doesn’t, then it was most likely an installation error. Check to see if you ripped any of the cables on the screen connections.
