Internal keyboard & trackpad quit working. Please help diagnose!
A few weeks ago my MBP A1260 (2.4GHz) suddenly rebooted out of the blue (never does that) and I subsequently smelled a bit of "burnt silicon" while it was rebooting. It didn't feel particularly hot (and the fans had been idling), but apparently it still had overheated. Then I noticed that neither the trackpad nor internal keyboard would work anymore.
Luckily, external keyboard/mouse do work (USB or bluetooth), and everything else still works fine.
I have googled high and low and unfortunately the one popular easy fix (touching/taping the flex cable under the battery) does nothing.
I have bought a replacement flex cable (the one that connects the main board to the top case and its components, including bluetooth) and tried installing that today, but still no dice.
Since the cable seems fine, I assume the issue is on either end of it: top case ($200-300) or main board ($600+).
The main board was replaced earlier this year (after a faulty nVidia blackout issue) and "looks" fine, as does the top case and trackpad circuitry. (No obvious signs of melting/overheating).
Is there any way I can further diagnose this, before shelling out any further $$?
Thanks for any pointers! Cheers