The freezer side of my built-in side by side Jenn-Air refrigerator (JS48FSFXDA) is having the following problem: during the defrost cycle, water is dripping from the ceiling of the freezer onto door shelves/baskets and elevator shelves and forming a coat of ice. From what I can see, it looks like the glass defrost heaters are working fine and melting the frost off the evaporator but the water overflows out of the drip pan and rains down on the shelves. I removed the evaporator drip pan hoping to find a clogged drain tube. I had to let the freezer thaw overnight because the drip pan was completely stuck in ice. No such luck, the drip tube was fine but had some ice in it where it meets the metal pipe coming out of the drip pan. I have tested the resistance in ohms of the foil drip pan heater, the glass defrost heaters and the drain tube heater. All readings were close to the numbers on the wiring diagram. I also tested the defrost thermostat and it has no continuity when warm and continuity when frozen. The temperature in the refrigerator section is staying around 37F. Is it possible that the defrost thermostat checks out OK but is still defective meaning that it ends the defrost cycle too quickly and that the drip pan heater and drain tube heater do not have enough time to melt the ice? Is it possible to test the adaptive defrost controller to see if that is the problem? Looks like the adaptive defrost controller is not all by itself but part of another board. Is it part of the main controller board? I also noticed a defrost thermister attached to the evaporator, is this part just for taking a freezer temperature reading for display when you open the refrigerator door or is it part of the adaptive defrost cycle? Thank you very much for your help.