Need Help on Refrigerator cooling issue. My maytag MSB2554AR side by side is not cooling the refrigerator side. I have found that the back side of the freezer gets frosted up. I cleaned the coils in back and defrosted the freezer coils. After about t weeks I am running into the same problem. Any suggestions?

There is most likely a problem with the defrost system. Since your refrigerator does not appear to have the adaptive defrost system, It will either be the defrost timer or the heater/terminator assembly. The heater/terminator part number is 61006116 with an approximate price of 60.00. The timer is part number 68233-2 costing around 80.00. The way to determine which one is causing your problem is to manually advance the timer into a defrost. The timer is located in the fresh food side, inside the control housing against the ceiling. You simply have to remove the light cover to access the timer. Put your fingers into the two rounded notches a few inches in from each side at the back, gently pull down and towards you. The light cover will release from the tabs at the back and the front, drop down and pull forward. The timer access hole is at the back right corner. The hole is about 1/2" in diameter with 2 1/4" screws, 1 on each side. Simply use a 1/4" flat blade screwdriver to advance the timer slowly until you hear a loud click. You must turn slowly or you will go too far. When you hear the first loud click, that is the defrost position. At that point, the heater below the evaporator coil (the one you defrosted in the freezer) should begin to get hot. If it does, you likely have a bad timer. If it doesn't, likely you need a heater/terminator assembly. The parts can be ordered online or from a local servicer. Let me know if you have any other questions.