Genuine Daikin 1984233 Outdoor Discharge Thermistor is the temperature sensor on the compressor discharge line that gives the system the reading it uses to protect the compressor. When it starts to fail, the outdoor unit may stop and start unexpectedly, lose output, or shut down to protect itself. A genuine sensor reads temperature the way your Daikin expects, keeping that protection accurate — where a non-genuine part can read off and leave the compressor unprotected.