Defrost Timer Location & Part Number

I believe I have a problem with the defrost timer or heater. My freezer is cold but the refrigerator side is warm. I cannot locate the defrost timer on the breakdown diagrams for my model. Can you advise on location and part number?
Thank you.

Your defost timer is behind the contol panel. You can test defrost by going to web site %url% to get specifics. Most probable failure is either the defrost thermostat on the evaporator,AP4299920 or the adaptive defost board, AP4340119

Thank you, I will check those items out.