Since you now have more than just a defrost issue now, I suspect the part that controls the defrost and all other functions of the refrigerator is experiencing a fault. This part is the electronic control, number 5 in the diagram, pictured below. This part tells the unit when to defrost and how long to run, so since you are having issues with both of these functions, I suspect it will need to be replaced. The correct part for your model is pictured and available below. If you need help installing it, please let me know. There is no charge for this follow up help!
Please let me know if you have additional questions or need clarification. There is no additional charge for any follow up help!
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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