GE Refrigerator Error Code S

Error code S on a GE refrigerator means the control board detected a thermistor signal voltage stuck at 5 VDC, which the board interprets as a shorted sensor. The thermistor is a temperature sensor that normally varies its resistance and signal voltage as the compartment temperature changes. A fixed 5 VDC reading tells the board the sensor circuit has a short, preventing accurate temperature monitoring.

You can continue using the refrigerator in the short term, but cooling performance may be unreliable. The control board uses thermistor data to regulate compressor and fan operation, so a shorted sensor can cause the refrigerator to run continuously, fail to reach target temperatures, or cycle incorrectly. Perishables are at risk if the compartment temperature rises. Address the S code promptly to avoid food spoilage and potential compressor wear from uncontrolled run cycles.

Unplug the refrigerator and disconnect the thermistor connector. Set a multimeter to measure resistance and probe the two terminals on the thermistor itself. At room temperature, most GE refrigerator thermistors read approximately 5,000 to 11,000 ohms depending on the model; check your specific model's service data for the exact spec. A reading of near zero or a dead short confirms the thermistor has failed and needs replacement. If the thermistor reads correctly in isolation but the code persists, re-examine the wiring harness for a short between the signal wire and the 5 VDC reference wire.

Start by unplugging the refrigerator and locating the thermistor wiring harness. Inspect the wiring for any pinched, chafed, or damaged insulation and check the connector for bridged pins or corrosion. If the wiring looks intact, test the thermistor resistance with a multimeter and compare the reading to the specification in your service manual. A shorted thermistor will typically read very low resistance or near zero; replace the thermistor if it tests shorted. If replacing the thermistor does not clear the code, the control board may need evaluation.

A replacement thermistor for a GE refrigerator typically costs between $15 and $40 for the part, and the repair is accessible to most DIY homeowners with basic tools and a multimeter. If a technician is needed for diagnosis and replacement, expect a service call fee plus labor, generally putting the total between $100 and $200 depending on your area. If the fault traces to the control board instead of the thermistor, board replacement costs range from $100 to $300 for the part alone.