BAT-LOWBackup battery lowWarningThe backup battery voltage is below threshold; ARD may be unavailable
Remedy: Check the charger output and replace the battery if aged
INV-FLTInverter faultCriticalThe VVVF inverter has signalled a fault and stopped the drive
Remedy: Read the inverter's own fault code; check motor, brake and power
MOT-THERMMotor thermal tripCriticalThe gearless motor thermal protection has tripped
Remedy: Let the motor cool; check load, ventilation and duty cycle
PHASE-ERRMains phase errorCriticalMissing or wrong-sequence mains phase detected
Remedy: Check the three-phase supply and phase order
SC-OPENSafety chain openCriticalThe EN 81 safety chain is interrupted; the car cannot move
Remedy: Identify the open contact (doors, limits, governor) and restore it
UCM-FAILUCM redundancy test failedCriticalThe Unintended Car Movement redundancy self-test did not pass
Remedy: Check UCM valves/brake and redundancy contacts; re-run the test