Released June 2012, Model A1278. Intel processor with Turbo Boost, Up to 512 MB DDR5 Video RAM

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Sparks? MacBook won't turn on..

so after solving this wifi no hardware issue (my sister got rice stuck in her macbook after trying to save it from water damage and there was still rice stuck) i've seem to have encountered another issue. as stated previously rice was stuck inside so I decided to wipe down the logic board and basically everything that's on the inside of the bottom of the case before closing it. now the macbook won't boot.. there is a dim green light displaying though... any solutions? I tried to reconnect the motherboard to the battery and now a certain part sparks and smokes up... PLS HELP

Update (01/02/2017)

that's the part that's smoking if you're wondering btw

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This circuit is for the T29 boost circuit (thunderbolt). PPBUS_G3H is used in this circuit, so it is possibly shorting 12v to ground. This would cause the smoke you are describing.

Clean the board first, since there is liquid damage still on the board. Check the bottom of the board too. Grab a schematic and boardview file (Google 820-3115 schematic) and measure PPBUS_G3H and PP3V42_G3H. Haven't got files in front of me at the moment, but you are definitely missing one of the X7R caps, think it is 4.7uf 10V or 25V, but check using the files.

If you do not have equipment to solder, take it to someone who can diagnose this properly. No point wasting time otherwise.

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ok will do, any idea how much this should costs? don't want to get ripped off, thanks!


I don't know where you are based, but I am in the UK and do logic board repairs for between £80-£150 depending on the complexity, some places do for up to £200. In the US, I imagine it would cost 200$-400$


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Brian will be eternally grateful.
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