EMC 2555 logic board dead

Question

MacBook Pro 13" Unibody Late 2011

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

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Emil Wang @macbookguy

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crwdns2893826:0crwdne2893826:0: Sun 11, 2017

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EMC 2555 logic board dead

Hello

i have this old EMC 2555 logic board from an macbook pro 13'' . I've tried to look at it to spot anything obvious, but i can't seem to find anything. it won't power on, when i plug the DC in, the magsafe flashes between a dim green and orange light and thats it. the power indicator is none responsive, even with a charge on the battery - it is completely dead.

any ideas?

i know you might say i should just buy a new board, but this is purely to see if i can get in going again

mayer im pretty sure its that one, heres some pics

https://s23.postimg.org/430fohw23/IMG_05...

https://s24.postimg.org/sc7owkd1x/IMG_05...

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1 Comment

@oldturkey03 it's one of two EMC 2555 2011 A1278

http://www.everymac.com/systems/apple/ma...

crwdns2893770:0Sun 12, 2017crwdnd2893770:0 mayer crwdne2893770:0

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Reece @reecee

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eFix Ltd (UK)

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crwdns2893826:0crwdne2893826:0: Sun 12, 2017

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Try a new DC jack to eliminate this being the cause. Grab a schematic and board view for 820-2936, and measure the power rails PPBUS_G3H and PP3V42_G3H. If these are lower than it says in the schematic, or not present, you need to investigate this further. Feel U7000 (charging IC) to see if it is getting hot, this can sometimes short to ground.

Beyond this, check the board for any brown probe points (indicates cleaned liquid damaged). I assume you have plugged it in without the battery connected too?

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Thanks, Ill try - where do i look for the schematics?

I have checked for the liquid damage, and nothing obvious - I have also tested it without battery too.

crwdns2893770:0Sun 13, 2017crwdnd2893770:0 Emil Wang crwdne2893770:0

Google "820-2936 schematics" and grab a board view too

crwdns2893770:0Sun 14, 2017crwdnd2893770:0 Reece crwdne2893770:0

Thanks man ill try

crwdns2893770:0Sun 15, 2017crwdnd2893770:0 Emil Wang crwdne2893770:0

crwdns2892346:0crwdne2892346:0

@oldturkey03 it's one of two EMC 2555 2011 A1278

http://www.everymac.com/systems/apple/ma... — mayer
Thanks, Ill try - where do i look for the schematics?

I have checked for the liquid damage, and nothing obvious - I have also tested it without battery too. — Emil Wang