Thanks for counting on us to help with your appliance problem. My name is ***** ***** I look forward to helping you! If the thermistors have been replaced, the issue has to be with the main control. That would also explain the lack of defrost. The control should toggle the defrost cycle every 12 hours of compressor run time, regardless of temperature, so the control is faulty and will need to be replaced.
The control is shown as number 6 in the diagram below.
The link below is to the part you will need from a highly recommended company rated A+ with the Better Business Bureau. They offer a 100% money back guarantee, EVEN ON INSTALLED ELECTRICAL PARTS, for an entire year! They are the only company to allow returns on installed parts for a refund and offer a FULL ONE YEAR WARRANTY!
Control <----- CLICK HERE FOR THE CORRECT PART FOR YOUR MODEL
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