Isolate issue.
Determine if the issue is caused by the device exhibiting any of the following symptoms:
Blank/Black Screen:
Device has power and is recognized by iTunes, but display remains black or is completely white.
or
Image Quality:
Distorted video, rainbow effect, poor image quality, non-uniform color, bad contrast, brightness or backlight issues, light bleed, horizontal or vertical lines or blocks, out of focus, or flickering.