The keyboard backlite cannot function after replace a 2nd hand keyboard from eBay. Believe the problem was from keyboard itself however the keyboard does have LED layers. And prohibited icon will be shown on screen when F5/F6 Keys (backlite control key) was pressed.
* the guide is good , thank you!
* if you looking for keyboard replacement only, steps 11-14 and 44-53 can be skipped.
* there is more than 40 tiny screws to secure the keyboard. Beware all of them are just too soft. don't play it so hard or you may have trouble to remove all of them.