Ice Maker Won't Drop Ice

Question

I have a Whirlpool side by side refrigerator with a new ice maker. The ice maker works fine but will not drop the ice. If I cycle the arm off/on (up/down) then it dumps the ice a few minutes later. Otherwise, the ice just sits in the tray. The ice maker is Whirlpool #4317943. Any suggestions on why it won't drop the ice or what to test?