I read internet troubleshooting articles, which said most likely cause was broken plastic gears in ice maker motor assembly causing ice maker to jam up and not rotate ice cube tray.
I purchased new ice maker assembly per my refrigerator parts list. It arrived in 2 days. Very easy removal and replacement (6 screws and 2 electrical connectors). Ice maker is working again making ice within a couple of hours.
Opened old broken ice maker assembly motor and found broken gears just as article said.