Troubleshooting for Outdoor Unit SiUS121502E160 Service Diagnosis7.17 Thermistor or Related Abnormality (Outdoor Unit)Error Code H9, J3, J6, J8, J9, P4Outdoor Unit LEDDisplayA j 1 i 2 i 3 h 4 h 5 hMethod of ErrorDetectionThis fault is identified based on the thermistor input voltage to the microcomputer.A thermistor fault is identified based on the temperature sensed by each thermistor.Error DecisionConditions The voltage between the both ends of the thermistor is above 4.96 V or below 0.04 V with thepower on. J3 error is judged if the discharge pipe temperature is lower than the heat exchangertemperature. The system is shut down if all the units are judged as the J8 error.SupposedCauses Disconnection of the connector for the thermistor Thermistor corresponding to the error code is defective. Defective heat exchanger thermistor in the case of J3 error (outdoor heat exchanger thermistorin cooling operation, or indoor heat exchanger thermistor in heating operation) Defective outdoor unit PCBTroubleshooting In case of P4Replace the outdoor unit PCB (main PCB).P4 : Radiation fin thermistorCautionBe sure to turn off the power switch before connecting or disconnectingconnectors, or parts may be damaged.
