Customer Questions and Answers for Refrigerator Defrost Timer by Whirlpool

Roberta, The defrost timer is a good possibility but it's a bit more common for the heater fail WP61002045 or a loose connection at the defrost thermostat or bad thermostat WP61005254 You'll need to remove the freezer back wall to access and check the heater, thermostat and wiring. Thanks and Good Luck.