The refrigerator compartment temperature sensor (also called an NTC thermistor) monitors the internal air temperature and reports it to the control board. When this sensor fails, the board cannot regulate cooling properly, leading to either a too-warm or too-cold fresh food compartment.
Common Causes
- Sensor wire has become disconnected or corroded
- The thermistor element has degraded over time
- Moisture intrusion has short-circuited the sensor
- Physical damage from a sharp object inside the compartment
Solutions
- Reset the appliance — unplug for 5–10 minutes. Temporary sensor glitches often clear on their own.
- Locate the sensor — it is usually clipped to the back wall or air duct inside the fresh food section.
- Inspect the wiring harness — look for broken, pinched, or corroded wires leading to the sensor connector.
- Test with a multimeter — a healthy NTC thermistor reads approximately 5,000–10,000 ohms at room temperature. A reading of zero or infinite resistance confirms failure.
- Replace the sensor — sensors are inexpensive and available by model number. Unclip the old sensor, disconnect the plug, and fit the new one. No special tools required.