"iMac Intel 27" Retina 5k Display Backlight don't work"に関する回答Personally I would write to Apple and explain your situation in a polite and full manner, include the photos and express how hugely disappointed you are that a computer that cost you X amount and is Y months old is suffering such a major problem. I wouldn't get aggressive or even quote any legal jargon - just set your case out and ask them what they can do about this. I would also suggest you send this e-mail to the Steve Jobs email address (firstname.lastname@example.org), this circumvents the first line of Apple customer care and puts you in touch with Executive Relations who have far more authority.
"Do I need to replace my motherboard?"に関する回答Not something you would want to replace your self there are many connections and the back has to come off the screen to replace it I would use a A+ certified Technician who has experience with this repair. I have done them however I am in Gainesville, Fl