Checking a GE Defrost Thermistor

Open the freezer door and locate the thermistor sitting near the bottom in the back of the compartment. Look for a sensor encased in plastic. Remove the screws around the casing and pull it away from the freezer wall. This gives you access to the thermistor.

Submerge the end of the thermistor in a glass of ice water for 5 minutes. Leave the thermistor in the water as you run the test.

Unplug the refrigerator and pull it away from the wall. Unscrew the sensor board cover. This will be a small access panel near the bottom of the refrigerator in the back.

Disconnect the connector labelled "J1" on the main board. Grasp the plug on the connector and squeeze slightly as you pull it away from the board.

Set the ohmmeter to read 16,000 ohms.

Insert the black probe on the meter into the fifth pin from the left of the J1 connector plug. A pin is a slot in the connector that holds a wire. The tip of the probe will slide into this slot.

Place the tip of the red probe into the third pin from the left of the plug. The ohmmeter should read 16.3 kohms if the thermistor if working properly. A reading above or below means the thermistor needs replacing.