I would double check all the logic board connections et pay special attention to the hard drive connector that must be pressed all the way down in its linear connector. Make sure that the bluethoot/airport card is well seated in the logic board. Don't clip the top case to the bottom case before completing internal verifications. Only connect the power button connector (blue & white wires) the its socket and try to power up the system.
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I would double check all the logic board connections et pay special attention to the hard drive connector that must be pressed all the way down in its linear socket. Make sure that the bluethoot/airport card is well seated in the logic board. Don't clip the top case to the bottom case before completing internal verifications. Only connect the power button connector (blue & white wires) the its socket and try to power up the system.
I would double check all the logic board connections et pay special attention to the hard drive connector that must be pressed all the way down in its linear connector. Make sure that the bluethoot/airport card is well seated in the logic board. Don't clip the top case to the bottom case before completing internal verifications. Only connect the power button connector (blue & white wires) the its socket and try to power up the system.