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Hello. I needed to get my wife’s old late 2009 MacBook A1342 working to press it into service for homeschooling. It had a faulty trackpad, which I replaced. While I had it open it clean it out as it was full of crud and dust. After reassembly, the keyboard doesn’t work properly, and pressure applied downwards on it cuts the power. Have I reassembled it wrongly? Is something shorting it out? Other than this it works normally, powers on, trackpad works etc etc. Just no way to log in as the keyboard doesn’t work, and it can cut the power randomly.
Review your logic board connections Reference: MacBook Unibody Model A1342 Logic Board Replacement
