Carefully dust off your logic board using a small soft paint brush and a can of can’ed air. Following the guides put everything back together. Do make sure you put the correct screws back to the correct locations.
Once everything is back together with just the battery disconnected, press the power button for 30 sec’s to make sure the logic board is fully discharged (leave the battery disconnected). Now plug in your MagSafe charger your system should spontaneously boot up. If not did the fan move a little or running?
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