Frigidaire Refrigerator Error Code Er rt

The Er rt error code on a Frigidaire refrigerator indicates a fault in the room temperature sensor circuit. Specifically, the control board has detected either a short circuit or an open circuit (disconnection) in the sensor or its wiring. The room temperature sensor is a thermistor, a resistive component whose resistance value changes predictably with temperature. When the control board reads a resistance value that falls outside the expected range, either abnormally low due to a short or essentially infinite due to an open circuit, it triggers this error code and flags the sensor circuit as failed.

The room temperature sensor monitors ambient air temperature inside or near the refrigerator compartment and feeds that data to the main control board. This reading is used to regulate cooling cycles and maintain proper temperature balance. A failed or disconnected sensor can cause the refrigerator to behave erratically, run continuously, or fail to cool correctly because the control board is working from inaccurate or absent temperature data.

The most common causes include a damaged thermistor that has failed internally, a wiring harness connector that has come loose or corroded at the sensor plug, or physical damage to the sensor wire. The first diagnostic step is to inspect the sensor and its connector directly, checking for loose pins, corrosion, bent terminals, or visible wire damage. If the connector checks out, the thermistor itself should be tested for proper resistance using a multimeter.