We recently went out of town for a week and because of a water disaster last year, I cut the water supply off to the house but didn't shut off the icemaker. A few days after we returned, I noticed ice wasn't being dumped into the bin. I got online and after several hours and numerous websites found the solution, (thankfully just before deciding to replace the icemaker).
Since I didn't shut it off, the supply line to the icemaker had frozen and wasn't letting water fill the icemaker. Using a hair dryer, I thawed the line and so far everything is back to normal.
Bottom line...if you shut off water supply to your house for an extended period, shut off your icemaker too.