2 Replaced Broken Screen, No backlight, changed fuse still not working
Hello,
I have a MacBook Pro A1502 EMC 2835. The screen was shattered so I replaced the entire screen upper assembly. When I replaced the screen, I made the mistake of not unplugging the battery connection from the motherboard. Once I was done with the repair. I turned the computer on, the screen was working and it showed the battery dead logo. So I grabbed a charger and plugged it in. Then the screen would not light up. I did the flashlight into the apple trick on the back of the computer and the screen does in fact work but no backlight. I bought and replaced the backlight fuse. I tested the old fuse and it was not blown but I replaced it with a new fuse anyway. The backlight still does not work. I checked again and I did order the correct screen. What else is there to check? What could I have possibly damaged by not unplugging the battery other than the fuse? I see in other questions here that it may be the LED Driver, where exactly is this located? I have another laptop I can switch the screens with to eliminate the screen from the equation.
What do you recommend? Thank you in advance.
Is this a good question?
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9 Comments
@deyth before you change more components like the LED driver, check to see if you have power to the fuse. Multimeter to DC Black probe on ground and Red probe on either end of the fuse. What do you get? You checked the display cable connector to make sure that there are no issues with that? Try your replacement (make sure it is the correct model otherwise you cannot use it) and let us know what you find out. Also, post some good pictures of your logic board with your QUESTION. That way we can see what you see.
by oldturkey03
@oldturkey03 thank you for the response and assistance!
I did not yet plug the board in and check for power at the fuse. I did a continuity check and found the fuse was not blown. I went ahead and replaced it anyway. This fuse is shown in the picture with the red circle. I can do what you're saying though. Just to verify, how should I go about powering up the board and checking this fuse in the proper way. The fuse is located underneath the board so it will have to be removed from the computer. I do not want to further damage anything else. I do not see any visual issues with the display cable connector. As far as the replacement screen, it would be from my personal MacBook pro that is in working condition. I am fixing this laptop for a friend. It is the exact same model and EMC number as mine. I would be able to swap the screens and eliminate that variable, but I am a little hesitant on doing this until I look into a few other things first since my laptop has no issues.
by Derrick Eyth
@deyth give us a good picture from the other side as well. Let's see if we can find out where you lose power to the backlight. I understand your hesitancy in testing with your personal screen. I'd be resistant to that as well :-)
by oldturkey03
@oldturkey03 I attached a picture of the front of the board. It is currently back in the computer as I was testing it. I can take it back out if you need to see it better.
by Derrick Eyth
That should work. Just one more. Can you try to get the dispaly connector and surrounding components a bit closer (without the cable) and the cable connector end itself as well? I know it's a PITA but internet repairs are difficult since you are our eyes, ears and hands.....:-)
by oldturkey03
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