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Lcd no back light

So a customer of mine let his friend work on their computer. The screen was originally damaged so they bought a new LCD that came assembled with the frame. The back light was not functioning. The customer came to my store with yet another brand new LCD assembly also doing the same thing with no back light. If I connect the computer to a TV using the HDMI port it works fine. I found that one of the chip next to the LCD connector looks damaged. However, if I use my multi-meter it will beep only if I touch the pins on the chip and not where its soldered to the motherboard. My question is if I apply a bit of solder to the chip would it be okay or should I just replace the chip. "P" chip tested fine, but looks a bit messed up. I provided some photos below. Any feedback is appreciated.

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Let us know the board number, which should be on the bottom right, since I do not think this is the 2012 version, most likely 2013 or 2014. Get a board view and schematic file for the board number, to find out the value of the components, or let me know the number and I will check.

You cannot resolder the burnt component (ferrite bead), that will need replacing. This part usually burnt when the LCD cable is chipped when connecting, which will also melt the inside of the LCD connector too (so would recommend replacing this too). You can shine a light inside the LCD connector and see if it looks slightly off. When this component is not working properly, you will not get any picture at all (not just no backlight).

Replace the backlight fuse for good measure too (part with the P on it). Looks a bit green around the ferrite bead, which would indicate liquid, but I am not sure if that is just a camera issue.

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Its a 2013 A1398 EMC 2867 model. I am not sure where I would be able to find a schematic file for the board. It would be great if you can recommend me the parts I need. The LCD connector looks fine as of right now. It doesn't seem off from the looks of it.

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Do you mean 2876? I can't find one for 2867. If it is, it will be a 2014 model. Verify this by checking the board number on the bottom left of the logic board (near where SSD plugs in). If it is 820-3662, the correct parts required will be below;

The component next to the LCD connector is a 220 ohm ferrite bead in 0805 package size.

The backlight fuse is a 3A 32V fuse in a 0603 package size.

Only replace the parts in the specification above if your board number matches, otherwise it may cause issues.

I would recommend replacing the LCD connector also, as whenever I have seen the ferrite bead burn, it has been caused by a chipped cable, which damages the connector too. If the connector is bad, when you plug in the new cable, it will burn the cable and the components you just replaced.

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Thank you. Its the MB number is the 820-3662. I will be ordering the parts from mouser.com

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Is this the right one for the fuse?

http://www.mouser.com/ProductDetail/Litt...

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Yes that's right

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