If my bottom-drawer freezer is left slightly open, the inside will frost/freeze up everywhere. Once this happens, after defrosting and cleaning it out, the door switch will not always turn on the light (or it will stutter), and the ice maker will not cycle. Replacing the switch fixes both these problems.
This is the second time I've had to do this, I think the switch itself has a design flaw. I'm guessing if water gets in the switch something gets messed up to not let a consistent "door closed" signal to the ice maker, preventing it from cycling.
You'll need two screwdrivers or a screwdriver and a auto trim tool to pull it out.