for me the issue is a glitchy connector for the trackpad cable.
Sometimes it works when I press down the frame between the trackpad and spacebar. Just now when I followed this guide
https://www.youtube.com/watch?v=FzcBL1NBtik
I realize that the reason it works is because the connector is pressed into the socket. But then it stops again after a while. So today I removed the connector shield and added extra padding to see if that stops the connector to stop dropping out of the socket.