Chosen Solution
I replaced keyboard, battery, fan…and trackpad ribbon cable and now only plugin keyboard and mouse are working. Trackpad not recognizing finger touches. please advise
This series uses a daisy chain approach for the keyboard and touchpad. Basically, we have the keyboard at the end of the chain which plugs into the touchpad and then the signals for both travel up the touchpad cable to the logic board. So replacing the touchpad cable won’t fix this! The touchpad its self is bad. Given the fact you replaced the keyboard hints of a liquid spill did you in. The touchpad also got damaged too! MacBook Air 13" (Mid 2013-2017) Trackpad and here’s the guide MacBook Air 13" Early 2015 Trackpad Replacement
Well, in my opinion, you should check if everything is plugged in correctly. If that dosen’t work them I recommend going to the nearest apple store.
