Defrost timer. Thanks for reply to my earlier question. It looks my refrigerator has defrost

Question

Thanks for reply to my earlier question. It looks my refrigerator has defrost problem. I tried to locate all the parts for defrost system, but couldn't find defrost timer. Where is defrost timer located for this Frigidaire, model: FRS24XGCW2.
I wonder if it has defrost timer.