Si-95 Failure Diagnosis for Inverter SystemTroubleshooting Inverter K Series 1133. Failure Diagnosis for Inverter System3.1 Points of DiagnosisThe main causes for each malfunction code are given in the table below. (For details refer to the next pageand those following.) : Failure is probable8 : Failure is possible : Failure is improbable— : Failure is impossibleMalfunctioncodeContents ofmalfunctionLocation of failurePoint of diagnosisInverter Compressor RefrigerantsystemOutdoorunit PCboardOther FieldcausePC boardpower unitOtherL4 Radiator fintemperaturerise — — — — Is the intake port ofthe radiator finclogged?L5 Instantaneousover-current 8 — — — — Inspect thecompressor.L8 Electronicthermal — 8 — — — Inspection thecompressor andrefrigerant system.L9 Stallprevention — 8 — — — Inspection thecompressor andrefrigerant system.LC Malfunction oftransmissionbetweeninverter PCboard andoutdoor unitPC board8 — — — —Inspect theconnectionbetween theinverter PC boardand outdoor unit PCboard. Next, inspectthe inverter PCboard.U2 Abnormalcurrent/voltage 8 8 — — — • Inspect the fuseon the inverter PCboard.• Check the DCvoltage.P1 Over-rippleprotection8 8 — — — — 8• Open phase• Current/voltageimbalance• Defect of maincircuit wiringP4 Defect ofradiator fintemperaturesensor8 — — — — —Inspect the radiatorfin thermistor.SI-95.BOOK Page 113 Friday, March 31, 2000 10:59 AM
