[jackr]

Took a leap of faith and removed the backplate to the lcd. The backlight consists of 27 leds on one side of the screen (the long side near the hinge). The lcd unit itself is a Innolux AT070TN92 V.2 AA0700013211 display. The mystery gets deeper as I found by holding the unit to light w/ the backplate and other pieces removed, the display part works fine. So what doesn't work so far is the led backlight and the touch sensor part.

I also counted the wires on the lcd cable, and it has 50 pins, which is the same as the ribbon connecting the lcd unit to the pcb that has the buttons and ir mouse. At the time when I had the backplate removed, I hadn't connected the pcb's connector (the black one with 12 pins) to the main board, so its likely that the touch sensor works.