When the screen is black and the green credit card reader light is off, but the refrigerator is still getting power, the first item to check is the surge protector. Most surge protectors deployed with Byte fridges have black and white power cords configured as follows:
To fix a black screen, unplug the white cable and plug in on the right side of the surge protector:
Wait 1-2 minutes for screen to reboot. Screen should be restored and back online within a few minutes.