SiUS181631EA Troubleshooting for Outdoor UnitTroubleshooting 2517.23 Radiation Fin Thermistor AbnormalityError Code P4Method of ErrorDetectionResistance of radiation fin thermistor is detected when the compressor is not operating.Error DecisionConditionsWhen the resistance value of thermistor becomes a value equivalent to open or short circuitedstatus★ Malfunction is not decided while the unit operation is continued.P4 is displayed by pressing the inspection button.SupposedCauses Defective radiation fin thermistor (FINTH) Defective main PCB (A1P)TroubleshootingRefer to Thermistor Resistance/Temperature Characteristics table 2 on page 268.Disconnect the lead wiresfrom the compressor, andthen check the compressorfor the insulation resistance.Remove and insert theconnector for the radiationfin thermistor X111A.TurnON the powersupply, and then checkwhether or not themalfunctionrecurs.Theinsulationresistance is low. (notmore than 100kΩ)Is theresistance of theradiation fin thermistornormal?CautionBe sure to turn off the power switch before connecting or disconnectingconnectors, or parts may be damaged.Completed.(R22104)Replace the compressor.YESReplace the main PCB(A1P).NONOReplace the radiation finthermistor.NOYESYESPower OFFPower ON
