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

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What blew up on the logic board?

okay... so something smoked sparked and then fell off when I plugged logicboard back into the battery. the other piece continues to smoke whenever I plug and replug... how to fix this?

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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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