Chosen Solution
I have an iPhone 7 plus that had minor water damage. Removed the screen, removed the logic board, cleaned out the entire device made sure it was 100% dried out. Replaced it all minus the screen. Used a new screen and attempted to boot the device. Red Battery icon with black screen. Perfect, just need to charge it right? As soon as the device acquired enough charge to boot. Black screen. No more battery icon. The device is detected by my PC and iTunes but the screen remains black. I can hear audio sounds from touching the screen and when the data/charging cord is inserted. I here sounds when I tap the screen, so it is detecting my fingers touching the screen but it remains black. Phone vibrates when I press the home button. Is this a hardware issue with the logic board? Update (03/06/2019) So the issue is power related. All of the screens I’ve tried are functional, just no backlight, therefore the screen appears black unless you angle it just right under very bright light. Does anyone have an idea on how this might be remedied or what components on the logic board may need replacing? Or could it be a battery issue, partially shorted?
Based on your description it does sound like the issue is hardware related. there must be some short on the board caused by corrosion that needs to be looked at. Do you know any micro-soldering technicians in your area?
have you tried the old screen(or a different new screen)?
