Dennis C Rockledge , FL June 01, 2018 Appliance: Maytag Upright Freezer MQF1656TEW02 Maytag Freezer Mqf1656tew02 / : Ice forming on back wall/blocking air circulation so non stop operation of compressor. How to replace Defrost Timer. Replace defrost timer. Do-It-Yourself Rating: Repair Time Estimate: Less than 15 minutes