Trackpad Does not Function Properly
Apple MacBook Pro "Core i7" 2.7 15" Retina 2012 Specs
Identifiers: Retina Mid-2012 - MD831LL/A
16GB RAM 750GB SSD card ( It was a $500 option on this model).
Machine came in "Out of Africa", with the trackpad not working. Running 10.11. It will move the curser a little bit and erratically. A wireless mouse was being used to navigate. I replaced the trackpad with a new one, also the battery at the customers request, ( he had me order these parts before I had a chance to see the machine). Problems persists. Ran virus check and caught a couple of minor Trojans and removed them. Problem persists. Booted from an external hard drive to see if it was a software issue 10.10.5. Problem persists. Safe Mode, persists. Works well with both wired and wireless mice.
I'm stuck. Machine was very dusty on the interior but I blew all of that out. Any ideas on where to look next?
Looks like there was a EFI Trackpad update for the 2012 MBP. A version 1.2 & 1.3. But they require 10.8 & 10.9 respectively. So i'm trying to install a 10.8 system on an external, download the update, boot from it and see if I can run it and fix the issue.
UPDATE 10/13 none of the updates will run on 10.11 system. Put in Target Mode, wiped the drive, did an internet restore to 10.8.5. Updates will not run nor will the trackpad work. I'm stumped. Senior Apple Tech is telling me to replace the logic board.
UPDATE 10/16 I have no idea of where to go on this one, without some help I'll have to send it in to Apple for a depot repair later today.