Customer Questions and Answers for Refrigerator Defrost Timer Assembly by Whirlpool

Linda, based on the information you have given it sounds as if you have a defrost failure. The defrost system consists of the defrost timer R0168027, defrost heater R0130430, and the defrost thermostat R0130427. You will need to test and replace the defective part. You can test parts by using a MultiMeter MA-DM1. Here is a link from our free repair forum you can refer to for help with using a multi meter. Hope this helps, thanks! http://forum.appliancepartspros.com/oven-repair-including-ranges-cooktops/4810-how-check-continuity-ohmmeter.html