I just have to say this because it's been a long journey and others may be having same issues! My evaporator fan and motor have been cycling on and off 24/7 non-stop for years! My dad finally decided to replace the evaporator fan and motor on my Frigidaire which is about 18 years old! We replaced evaporator fan and motor which wasn't the issue! We then changed the defrost thermostat which also was not it so I came on to this site and saw others having same issue! I saw a few ask the question and this site said it's probably a wonky defrost control panel! After changing three other parts we just changed the defrost control panel and that was it! Refrigerator is running perfectly now and evaporator fan is doing what it's supposed to cycling to get to temperature and then it shuts off and there is no more constant cycling! Thank you to this site for giving us a place to research!