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Macbook Pro was working fine last time I used it a few weeks ago. Its been powered off since. Started it up today and the keyboard and trackpad dont work. Connecting external keyboard and mouse work fine. Cant boot in safe mode to troubleshoot, again because the built-in keyboard doesn’t respond.
Apple loves making things complex! If I remember correctly the TouchPad logic is also the USB driver logic for the keyboard. So I’m suspecting you might have had a spill or you used some cleaner which seeped under neath damaging the logic board. Here’s the needed part MacBook Pro 15" Retina (Late 2016-2019) Trackpad and here’s the guide to put it in MacBook Pro 15" Touch Bar Late 2016 Trackpad Replacement While you’re in their check the keyboard cable connector for any corrosion
