Chosen Solution

Replaced boards , evap fan, and both door switched. Defrost heater won’t come on

Cause 1 The Evaporator Coils are Frosted Over The defrost heater assembly turns on a few times throughout the day to melt away any frost that may have accumulated on the evaporator coils. If the defrost heater assembly is defective, frost will continue to accumulate on the evaporator coils, and the coils will become plugged with frost. If the evaporator coils are frosted over, the airflow through the coils will be restricted, causing the refrigerator not to cool. Check the evaporator coils to determine if they are frosted over. If the evaporator coils are frosted over, test each component of the defrost system. Cause 2 Damper Control Assembly The air damper control opens and closes to let the proper amount of cold air into the refrigerator compartment. If the damper does not open properly, it won’t let enough cold air into the refrigerator. Check the damper control to determine if it is broken or stuck closed.