What can cause a blank black screen on iPhone 5S?
I am trying to repair an iPhone 5S. I have tested its LCD, and it is working perfectly. I connected the phone to a laptop, and iTunes just responds correctly as if it is a normal iPhone, displaying its information, contents in memory, etc. But there is nothing on the iPhone screen. I wonder if there is anything other than the logic board that can cause zero video output to the LCD.
Is this a good question?