Chosen Solution
2 days ago I was opening my MBP (13.3" mid 2012) trying to figure out why the right hinge does a strange sound when closing the lid, watched a few tutorials on YouTube and I opened up the laptop, I disconnected the flex cable and accidentally dropped it on the motherboard, something did a short and now the laptop works fine but no backlight on the screen (Did the apple logo test) I had the exact same issue (and situation with the exact same last 4 serial digits) that this guy had: Backlight not working found fuse open circuit Any help please? I almost cryed mi eyes out LOL
Finally decided to get an used Logic Board for around $200, now the Mac works pretty fine, this means that the problem was not the LCD but the backlight fuse, I know this was the easiest solution but I don’t trust the component-level technicians here in Chile.
With help of luck you have blown the backlight fuse. To be able tell you need a multimeter to test the fuse if its good or bad To be able to fix you will need a Soldering station and skill. If the fuse is good then things gets more complicated but if the fuse is bad needs to be remove and replace with good one then see if it will fix the problem. google (a1278 backlight fuse )and see how Louis does . I hope it helps . Thanks .
It’s either backlight fuse, drive chip, lcd or lcd cable. Start with LCD first. Thanks.
