Thank you for your question.
I have checked the model number you have submitted. The defrost timer is located on the unit control board in the refrigerator section of the refrigerator. If the timer fails the control, board has to be replaced. I suspect you are having a defrost problem with the refrigerator. If I have assumed correctly you can force the refrigerator into a defrost. I have provided you with a copy of the tech sheet below. Use the tech sheet to enter the diagnostics on the unit control. Once in service diagnostics go to step six. This is the forced defrost.
I hope this helps.
If I can be of further assistance, please feel free to reply below.
Here is a link to order any parts you need.
Sears Parts Direct
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services
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