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Mid 2012 model, A1278 / 2.5 GHz i5 or 2.9 GHz i7 processor.

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Burned component close to lvds connector

We were changing the sata cable and we removed the motherboard for cleaning and changing the thermal compound.

In the process, we did something that broke one component close the the lvds connectors, which happen to be burned.

Strange thing, is that the computer work fine in the first boot, only in the second this happen.

Can someone try to help us get the right components in that area (depicted in the picture) for trying to get a new ones to see if we can get the screen alive.

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Update

Thank you very much for you answer.

It is difficult to get a better photo, we only have an iPhone to take the pictures.

The last 4 digits of the serial number are DV30.

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Bruno Almeida, give us the last four digits of your computers serial number. That will help us to properly identify your computers hardware.

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That's an 820-3115 board. Just buy a dead board for forty bucks and copy the stuff over. By the time you buy a boardview, buy a schematic, and go nuts finding what you will wish you had just bought a parts board with everything you need and the locations of the proper parts right in front of you.

In this case you &&^&@@ up two inductors for the PP3V3 power rail to the LCD L9004 and L9008. Expect U9000 to be dead, as well as burned pads on pin 1 of L9004.

L9008 is used for the initial EEPROM/EDID detection by the computer of the LCD. Once detected and handshake is complete, the PCH will turn on the LCD via U9000 which goes through L9004. L9004 protects U9000 from damage since U9000 is easily destroyed.

Common cause is turning laptop on with LVDS lopsided, do not do this again!

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I have the exact same problem. Schema's can be found online for free. I figured out this is a L9004 which is a 120 Ohm 1.5Amp ferrite bead, or ferrite choke (from another Ifixit post). A Murata BLM15EG121SN1D will be a perfect match. I tried to replace it, it is extremely challening. I used a magnifying glass and a very thin soldering iron. I was able to solder on a similar component from another board but that did not work. Maybe it's wrong :). I still get a white screen only. I wonder if anyone had this and fixed it? In my case this was caused by liquid damage and while all worked fine before taking it apart and cleaning it, it turned out that the soft material pressing on the connector seemed to short circuit it. best to throw that away I think.

Any updates of people trying to fix this are greatly appreciated :)!

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Vincent, use a hot air station to solder this component on, a lot easier. It will need to be the exact same component as in the schematic.

If it is showing a white screen still, this component is the cause, it will always just show a white screen if this is burnt out. You may need to solder a wire to one/both sides, usually the solder pads burn out, or it doesn't get continuity properly.

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Hi Reece, thank you for the quick reply. I am pretty sure the part I put in was making contact, it was 140 Ohm and came from a Dell power board. Do you think the U9000 may be fried too? Or would my part not be connected properly, or ignored because of the value? I was expecting at least some image. I have a hot air station, but as you mention the pads are damaged (not completely gone). I will order a L9004, do you or anyone happen to know what the U9000 is in part number? Is there a way to figure that out? Any approach to voltage measuring is also highly appreciated, I am pretty new to this.

Thanks everyone for sharing!

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Bruno Almeida, right now it looks like you are missing reference designator L9004 which is a 120OHM 1.5A filter (inductor) in a 0402 package. You may want to consider a clear close up to verify this. Also, give us the last 4 digits of your computers serial number to absolutely verify the part.

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