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I replaced the battery on my 15” MacBook Pro w Retina display mid2014 using an ifixit kit and following all the directions. Battery powered up but now the display screen is not working. I went back and checked all the steps and all seems good. Any ideas what it could be?
It does sound like you missed a step or damaged something in the process. Go back to the guide and compare the parts with yours look very carefully MacBook Pro 15" Retina Display Mid 2014 Battery Replacement.
