So... I was finally able to find a donor VZC to replace the swollen battery in my original VZC. However, when I put it back together, I lost internal video. External video still works, and that is how I'm able to make this post now. Weird thing is, if I swipe in from the right on my VZC, the Action Center still comes up on my external display. If I swipe in from the left, I get the Task View. So my touchscreen is still working, It's just that the display is dark. Display Settings detects just the external display. So... I assume I did something wrong in re-installing the notoriously fragile u-shaped display ribbon cable (FONE_DB_FPC). I've tried re-seating it a couple of times now with no change in outcome. I'm nervous that if I keep tooling with it, I'll lose even the touchscreen (not that it's useful without the display). Have I damaged the cable? Is there some trick to installing it? I'd order a new cable if it were possible, but I know from past negative experience that VAIO support is not worth contacting. They don't sell parts. They'll fix it for you for a minimum of $300. I wonder if they deliberately engineered this cable to be one time use -- almost as a way of doing chassis intrusion detection. Still dreaming of the day I can afford to replace this thing with a Surface Book 2.