Chosen Solution
Based on Internal keyboard & trackpad quit working. Please help diagnose! it looks like the trackpad and associated electronics from my top case are dead, resulting in the internal keyboard & trackpad not working anymore, while the other components (Bluetooth controller) still work. So now I’m considering replacing the trackpad and especially its logic board (the one under the battery, to which the keyboard and main board flex cables connect). Ideally I would like to replace just those parts, so I can get a much cheaper cosmetically-damaged replacement top case, and reuse mine (which looks great) instead of having to shell out several $100 for a new (or even used) top case. Is such a replacement possible? Or would it invariably involve dirty hacks that would leave scars, like sawing the top case and the like? The trackpad and PCB unit seem to be point-welded (not sure of the term/technique) to the back of the top case, and I’ve no idea if that can easily be opened and redone… Thanks for your thoughts, dear iFixers!! Cheers.
I did a bit of research into this today. On the little board underneath the trackpad is a chip labelled “CX8024994-2” which i believe is the USB controller for the topcase. A Google search returned nothing, though. Anyway, i took my smallest soldering iron (a 25W Weller with a tiny tip) and a good magnifier and resoldered all the little legs. Hey presto, it works! You might not have to change anything at all.
