[Alex2]

Plz help: to initiate defrost cycle manually; Adaptive Defrost Control model - no mechanical timer, defrost controled by electronics. I now how to do it in Whirlpool, Frigidaire, Amana - but don't know how to do it for GE . Model GSH25JSTA SS. Thanks ...

[applianceman]

You can jump out the heater but I don’t feel it is necessary. This is the heater most of the time but sometimes it is the thermistor and can be the main board or the defrost thermostat.

If you like you can diagnose this before you melt the ice from the main board. Unplug the refrigerator and the connections you check. Check the thermistor from the main board at the J1 connector pin 5 to pin 4 with the thermistor covered in ice it should be at or around 16.3K ohms. If it is off by more than 5% replace it. For more on this

Testing A Refrigerator Thermistor On A GE Refrigerator

Now at the bottom of the board there is a blue plug on the left one of the terminals is marked def J9 (defrost) and on the white plug there is a pin marked N J7 pin 9 (orange wire) check for continuity from the def to N. If it is open the heater or the defrost thermostat is bad. Check the heater once the ice is melted and if it is bad replace it and if not replace the defrost thermostat.

If the thermistor, defrost thermostat and the heater check ok replace the main board.

GE Refrigerator Repair Guide


If you unplug that blue plug and make a jumper to jump from defrost to line and plug the refrigerator in the heater will come on but I don’t think it is necessary.