Review on Supco SC952 Refrigerator Defrost Timer: GE WR9X489 Compatible | High-Quality Replacement - 162D6022P16, AP2061695, PS310858 by Kyle Gresham

When defrost isn't working properly, frost and then ice will cover the cooling elements, greatly reducing the ability to cool the circulating air. The most common reasons for not defrosting are this timer or heating elements. There is no definitive way to determine the real reason without technical knowledge. But you can try replacing this timer just to see if it fixes the problem, you need basic hand tools and there are some videos online showing the process. Disconnect the refrigerator from the power supply before doing this work. Wiring with a timer is dangerous, even if you turn off the refrigerator, you have to unplug it. After replacing this timer, you need to open the back of the freezer (from the inside) and let the frost and ice melt. After that, plug it in and hope the timer fixes the problem. If not, the heating elements are the next part, and if you can't handle that, you may need a mechanic to take care of it.