Has your Apple iPhone 7 backlight circuit failed? Is it causing a blank display on the screen? Does the device seem fully operational apart from the display functionality? The usual symptoms of a faulty backlight ; The smartphone seems to be fully functional apart from the fact that there is no image on the display The user has repaired the screen/display on the smartphone and failed to disconnect the battery beforehand The device has been disassembled and when reassembling the screen has stopped working The device was dropped or it has been in contact with liquid