I have a bottom drawer freezer/ refrigerator. My refrigerator section was warm; freezer section was cold. No air was coming out of the vent in the fridge so I thought that the fan was not working. Looked up the fan for my fridge on AppliancePartsPros & they had a video on how to get to it and replace it. The fridge in the video appeared to be my model. Removed everything shown in the video to get to the fan only to discover that the fan worked but the evaporator coil and the defrost thermostat were frozen solid. The video was thorough. Comments on the site suggested one of three causes for my problem: defrost heater; defrost thermostat; control . Obtained a spec sheet for the fridge and found a youtube video on how to test the cable and thermostat. The cable checked out ok but the defrost thermostat did not. Ordered the part from AppliancePartsPros.com and received it the next day. Installed it the following day and so far, so good. Hint: the video for the evaporator fan was for my fridge; the video for the thermostat was not. The basic procedure was illustrated but it was not the exact one for my brand/model. You might want to try a video for other parts in the same area of your appliance if the video on the page for your part is not for your model.