Logic Board, per Genius Bar fellow at Atlanta-Lenox. Several hundred $. I'm 70, more time than money and always a fixer & putterer. But larger, mechanical items - cars, mostly. A computer whiz sent me the iFix link
So far, so good. I'm on Step 13 & on pause, partly because of T-Giving
More light on the innards, please. The photos are excellent, but I think the camera is thrown off by the fingers, doesn't get the dark details of the cables, etc., so well.
I am using magnets to keep the tiny screws organized, and labeling everything. I'm working in daylight hours, next to a window, occasionally using a magnifying glass.
I'm glad that I ordered the spudger, though a sturdy bamboo skewer might have done the deed, I did not want to risk it.
Stay tuned and thanks for this quality site!