I,m having trouble with my refrigerator. the frizer side is working fine but the fridge is warm i took the pannel inside the fridge and the eveporator coil is frosted i replaced the sensor ass item number AP4136839 and nothing. im thinking that the defrost cycle is not working. after unpluging the refrigerator and defrosted the coil the frige works fine for a day or two until ice buid up again. a tech replaced the main board approx a year ago. do i need to replace the main board again or is something else i can check
thanks for your help in advance.