Here is a solution for iphone 5,5s, 5c backlight issue or black screen only not blue screen .
Lcd board connector's 3rd pin is directly goes to backlight fuse and backlight fuse goes to diode and quil. First change the fuse , if this doesn't work then change diode and L quil. Diode and quil are located next to the big Apple power ic. If that does not resolve the problem then you guys must have used LONG SCREW after replacing the lcd. So in cases where long screw has been used ,the phone will show BLUE SCREEN, and Error 09 or 14 when restoring on itunes.