wordi pressi the backlight fuse is reference designator F8400. It is a 32V 3A fuse in a 0603 package. Location on your logicboard as shown. Measure continuity with a multimeter or your can measure for proper voltage with the board power applied.
[image|2731180]
If it is not the fuse,you will have to check deeper for the cause. Use the schematic for the backlight as provided. Do not forget to check your display connector since a lot of short circuit happen right there. Post some images of your logicboard (both sides) with your QUESTION so we can see what you see.
[image|2731181]
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