Four days ago, refrigerator freezer & fresh food compartment started not cooling properly. Day 1- heard a loud clunking noise (as if ice caught in a fan) coming from freezer compartment, opened freezer door, noise seemed to be coming from evaporator fan area. Noised then stop, with hours Refrigerator/Freezer temperature dropped to 60+ degrees. Lower half of both were colder. Opened freezer compartment back panel, coils completely frosted over and evaporator fan not running. Purchased & installed new evaporator fan w/sensor, this did not solve the problem. Then purchased and installed defrost thermostat, and defrost heater. But, problem still exist. This was to be a week of vacation, that has turn out to be a nightmare. I am at my wits end, and need assistance ASAP.

Thanks, I thought as you quoted the only thing left to replace would be the motherboard. I am going now to purchase one, I'll will let you know my progress.