Maytag side by side refrigerator and some top mount refrigerator’s have a common issue. If your model has a adaptive defrost control board it is probably bad, lets test and find out. You will need a volt meter to verify which component is bad.
When the refrigerators adaptive defrost control fails, the refrigerator never goes into defrost, thus causing a build up of ice on the evaporator coils. When the ice build up happens it cuts the air flow off to the refrigerator section. The evaporator fan will not be able to pull air through the evaporator and push it into the refrigerator section.
On the Maytag style side by side start by removing the back panel and defrosting the top half of the evaporator. The back panel is held down with two screws once removed the lower back panel will lift out. This will enable you to make the proper test at the heater and defrost thermostat.
Once inside the freezer compartment you will need to disconnect the heater and thermostat wires. Here is what the two parts should ohm out at.
-Defrost heater (30 ohm)
-Defrost thermostat (Less than one ohm)
If both of these parts test within spec then the adaptive defrost control board is the fault.
The adaptive defrost control is located in the refrigerator section in the light bulb housing. You will need to remove the housing to access the adaptive defrost control. Here is how to do so.
Remove the plastic housing cover the controls. On the back side there are two finger grooves, place pressure downwards and pull forward the plastic housing will slide forward and out.
Now there are two screws that hold the clear plastic temperature indicator remove them, directly behind and beside the light bulb there are two more screws remove them. On the back middle of the housing you will see one more screw, by removing it the housing will come down reveling the adaptive defrost control board.
On some model the control is held down with two screws, if your model is newer or the control has already been replaced then the board will lift out of the housing. Take the wire harness of the control and install the new board.
You will need to defrost the freezer section and clear all of the ice before restoring the refrigerator back to normal operations. Not clearing the ice will result in the unit never getting back to temperature and possible loss of food.