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I replaced top case keyboard for someone and the keys aren’t working still so I tried a new logic board and still having an issue where its delaying the letter typed or doesn’t even work at all any idea what else it might be?
Hi! What all exactly did you replace? Ive had a lot of these MacBook Air Retina models where a bad battery can cause all sorts of weird issues or glitches. These computers do not work right at all if the battery has been damaged or is defective. You said that you replaced the topcase, did it come with a battery as well? Also the trackpad and or trackpad cable or the trackpad connector board can cause similar issues with the keyboard or functionality of the MacBook. The audio board on these can also cause problems, try testing it with the audio board flex disconnected from the motherboard.