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I just changed the speakers, and when I assemble everything step by step, the mac does not turn on and I checked everything, disassembled and reassembled and I’m still the same, any suggestions?
Sounds like you need to find a second set of eyes to review the connections. Review this guides connections MacBook Pro 15" Retina Display Mid 2014 Logic Board Replacement What is the color of the MagSafe LED? Amber or Green or not lit.
