Unplug the refrigerator, remove the wire from the "defrost" terminal on the control board and measure the resistance between this wire and the neutral orange wire (pin 9 on the J7 connector). The freezer must be cold at this time.

If the reading is about 22 Ohms then the main control board has to be replaced. It is recommended to replace the board together with both freezer thermistors.

i have a ge model #gbs22kbpabb that the defost system is not working. i tested the conector as stated above and got 15 ohms. i have tested the heater itself and got 31 ohms. also tested the thermistor cold and at room temp. and have continuity both ways. not sure where to go from here. any help would greatly be appriaciated.

thanks
dave