Chosen Solution
Hi. iPhone6plus screen cracked and was left unused for months. I got new screen form ifixit, but after change phone does not “start". It power on and with a flashlight I can see a apple logo on the screen coming and going. So infinite loop with no backlight on the screen. Visual check says that cables and connectors are ok. Can a dead battery do this? Logic board? Thank you.
If you didn’t disconnect the battery while doing the screen repair, you probably shorted out the backlight circuit resulting in no backlight or a “blank” screen. You’ll need a board repair specialist to fix this issue as it results in a blown fuse or capacitor within the backlight circuit. It is not a repair you can DIY as it requires a lot of skill and thousands of dollars in tools.
