Customer Questions and Answers for Refrigerator Ice Maker Assembly by Whirlpool

Tim, The sensor would be located on the icemaker itself and to test the bottom icemaker you would need to make sure that you push in on the light switch so that it can cycle. The freezer icemaker does not run through the control board so it would not likely be the control board. Check to see if it is getting water into the icemaker or if there is ice in it. For the upper icemaker if it is saying there is a thermistor issue then this will be part of the icemaker.