SiUS091601E TroubleshootingService Diagnosis 704.2 Indoor Unit PCB AbnormalityError Code A1Method of ErrorDetectionThe system checks if the circuit works properly within the microcomputer of the indoor unit.Error DecisionConditionsThe system cannot set the internal settings.SupposedCauses Wrong models interconnected Defective indoor unit PCB Disconnection of connector Reduction of power supply voltageTroubleshootingNote: Check the following connector.Check the connection ofconnectors (See Note.).Correct the connection.OK? Check the power supplyvoltage.Start operation.Voltage as rated?Error repeats?Check the power supplyvoltage.Start operation.Voltage as rated?Error repeats?Error repeats?Combination ofthe indoor and outdoorunit matched?YESNONOYESNONOYES(R20486)Caution∗ To secure the connection,once disconnect the connectorand then reconnect it.YESNOYESNOYESNOYESMatch the compatiblemodels.Correct the powersupply.Replace the indoor unitPCB (control PCB).Completed.Completed.Correct the powersupply.Replace the indoor unitPCB (control PCB).Completed.Be sure to turn off the power switch before connecting or disconnectingconnectors, or parts may be damaged.Model Type Connector09/12 class Terminal board ~ Control PCB (H1, H2, H3)15 class Terminal board ~ Filter PCB (S100)
