Backlight issue fuse good

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MacBook Pro 13" Unibody Late 2011

Late 2011 model, A1278 / 2.4 GHz i5 or 2.8 GHz i7 processor.

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michael johnson @vans113

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Posted: Apr 11, 2016

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Backlight issue fuse good

So I came across this MacBook from a friend and originally it had a cracked screen. The backlight worked at this time. Well she was given a free screen swapped it over and the backlight doesn't work ( could be why it was free) well I have done research and seen about the fuse I took the back off powered it up and I have 10v across the fuse when on and I can see items on the screen with a light shined on it. Anything else I should check before ordering a new screen? Thanks!

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So I got a used screen off of ebay and doped it in. same issue. I have about 11V across the back light fuse and some of the pins on the controller have some resistance on them. is there anything else I should check for or part it out at this point? I picked this up cheap hoping for an easy fix , and I don't want to dump in money for a new logic board at this point. The laptop was working fine the screen was stepped on, and it's had this issue ever since.

Apr 20, 2016 by michael johnson

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oldturkey03 @oldturkey03

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Posted: Apr 11, 2016

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michael johnson most often it is the backlight circuitry on the logic board that shortens out. you computer does not have an inverter cable per se and the LCD is most often not affected. If you want to replace a part, I'd go with the logic board, but check your old one first. Clean it appropriately with isopropyl alcohol and check the fuse and other components, for any damage. Check your display cable connector and make sure it is seated properly and check for damage on it as well.

Fuse and LED driver location marked. The driver is a APP001A and that of course means it is Apple proprietary so no data sheets available. It might also be impossible to get a replacement. You'll have to find some information about Apples LED driver and see if there is a compatible one from TI for example.

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How do you check the led driver? The fuse has power acrossed it when on 10v to be exact. So my fuse is good. If the driver is good also could the screens backlight have just burnt out also?

Apr 12, 2016 by michael johnson

Imhad the same problem, and tried the isopropyl alcohol on the backlight fuse. Worked like a CHARM! I noticed some corrosion upon checking it using your illustration above. Thanks a million bro. Your a lifesaver. Well at least a MacBook Pro saver..

Feb 26, 2018 by richard butts

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So I got a used screen off of ebay and doped it in. same issue. I have about 11V across the back light fuse and some of the pins on the controller have some resistance on them. is there anything else I should check for or part it out at this point? I picked this up cheap hoping for an easy fix , and I don't want to dump in money for a new logic board at this point. The laptop was working fine the screen was stepped on, and it's had this issue ever since. — michael johnson
How do you check the led driver? The fuse has power acrossed it when on 10v to be exact. So my fuse is good. If the driver is good also could the screens backlight have just burnt out also? — michael johnson
Imhad the same problem, and tried the isopropyl alcohol on the backlight fuse. Worked like a CHARM! I noticed some corrosion upon checking it using your illustration above. Thanks a million bro. Your a lifesaver. Well at least a MacBook Pro saver.. — richard butts

Seji the veggie @skimmilk05 Rep: 1.9k 7 6 1 · Answer 1 · 2016-04-11T19:46:12-07:00

Seji the veggie @skimmilk05

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It means the backlight burned out. You can choose to replace the backlight on its own, but this repair is risky and very difficult since the LCD and backlight are fused together. Additionally, there are mercury components.

Replace the MacBook Pro 13" Unibody (Early 2011-Late 2011) Display Assembly.