The refrigerator defaults to "always on" when the thermistor has trouble reading the temperature. Sometimes from wind, sudden changes in outside temperature, or ice or other contaminants on the fin where the probe is connected.
The probe has a wire on it and slides on to the far right fin inside on the refrigerator. First shut off the refrigerator. Then slide the probe towards you to remove from the fin, and clean the fin were it was attached. Re-attach the probe to the fin. Turn refrigerator back on and it should reset and start working again.
