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

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help identifying my components

My Macbook is a MacBook Pro 13" Unibody (Model A1278 Late 2011) 2.4 GHz Logic Board

Do you have the Electrical Circuit Diagram for me?? If not, can you help identifying my components

I think these are 2 capacitors. I really hope you've the electrical circuit so I can measure maybe if more is damaged. Thank you

Thank you

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Update

Dear OldTurkey03,

I soldered the components, measured and all looked ok. Put all cables and connectors back in place, but without success.

See my picture with comments. Hope you can help me further. What testpoints can I use? Where can I find the Output voltage? The led of the charger is not going on. Thanks a lot already!!

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Dear Oldturkey03,

I ready this post of you as well. MacBook Pro 2011 not charging

I took a good battery out of another MPB and put this one in the MBP that I want to fix. With the new battery in the MBP, I press the button on the side of the battery indicator, but the green light of battery indication does not light up. Also the charge light does not light up. seems to be something with the charging circuit / power circuit. Can you guide me more in order to trace the right components that might be damaged?? Thanks!!

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Jan van Iersel, check the direction of the capacitors! looks like you soldered one of them on wrong. Compare your 2nd and 3rd picture ;-)

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Jan van Iersel, both components are identical. They are:

Reference Designator C3890 is a 10UF 25V 10% X5R Capacitor in a 0805 package

Reference Designator C3891 is a 10UF 25V 10% X5R Capacitor in a 0805 package

The capacitors are part of the 15V boost circuit

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Dear Oldturkey03 :)

Many thanks for your help on this!! I hope by replacing the components that the Macbook is working again! The traces are rusty, so I cleaned them with alcohol, hope I can put some solder on it later on and that it works again. I really hope these two components are the only ones that needs to be replaced. There was never a liquid spill over it, so this is a luck. I'm just a victim of a bad prodcution of logic boards of Apple.

I will let you know the result or if I need more help :-)

Thanks!!

Jan

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Dear Oldturkey03,

when I look at the schematic. Do you think by missing these components can cause the laptop will not boot? I don´t think so or am I mistaken?

thank you

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I am sure it could since you are most likely missing the higher voltage.

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wil let you know. I could only order 50pcs of these capacitors, so if you need a few, let me know and I will send to you for free.

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Wow, you should have let me know, I would have send you less than 50pcs :-)

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Jan van Iersel will be eternally grateful.
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