Unibody MacBook Pro models with 13" displays produced from 2009-2012.

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No Power Up even Battery LED show fully charged

I need some support advice for my 2009 Macbook Pro Core2 duo.

After a while of not beeing used, but still connected to the charger, the computer would not start any more.

The battery status is responding, all LEDs show green, fully charged.

The charger connector shows the same, green LED on, battery fully charged.

I tried the SMC resetting procedure, no effect.

I opend the case, checked the cables, it all looks fine.

Also unpluged the battery and pressed the power button 10s, waited 30s, reconnected, no effect, also no SMC resetting shows any result.

The powerbutton and the loudspeaker are wired together to a 4pin connector. I tried to measure if the power on switch is working, is always shows 7.5Ohm, connected, unconnected, and unconnected with pressing the power connector. Is that normal?

Any other check that can be conducted?

Thanks a lot for any further acvice.

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Thanks Reece for your fast reply.

I realised that the power button is not on this 4 pin plug, that contains the loud speaker cable.

So my measurement where not the right one.

Is there a way I can check if the power button is working without replacing the whole keyboard?

Other then on other logic boards, I did not find any information of the power button test pad.

Thanks a lot for your support.


Measure the voltage on the 5th pin of the keyboard connector (from left to right, without touching another pin as well) whilst pressing the power button. You may need another person to do this.

If the power button is working, the voltage will drop very low when it is pressed. If it is changing, but not momentarily dropping to under around 0.8v I think (or it is not changing when pressed), the keyboard is bad.


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Try plugging in a new keyboard. Remove and check the logic board for liquid damage.

The power button and speaker are not wired together, the power button is a part of the keyboard on this version.

Do this first, then take it from here.

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Thomas Gunther will be eternally grateful.
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