Garmin G1000 Cockpit Reference Guide for the Cessna Caravan190-00748-00 Rev. C 53Abnormal OperationFlightInstruments EISNav/Com/XPDR/Audio AFCS GPS NavFlightPlanning ProceduresHazardAvoidanceAdditionalFeaturesAbnormalOperationAnnun/Alerts Appendix IndexABNORMAL OPERATIONREVERSIONARY MODEShould a system detected failure occur in either display, the G1000 automaticallyenters reversionary mode. In reversionary mode, critical flight instrumentation iscombined with engine instrumentation on the remaining display. Minimal navigationcapability is available on the reversionary mode display.Reversionary display mode can be manually activated by pressing the DISPLAYBACKUP Button on the audio panel.NOTE: The Cessna Caravan Pilot’s Operating Handbook (POH) always takesprecedence over the information found in this section.ABNORMAL COM OPERATIONWhen a COM tuning failure is detected by the system, the emergency frequency(121.500 MHz) is automatically loaded into the active frequency field of the COMradio for which the tuning failure was detected. In the event of a failure of both PFDs,the emergency frequency (121.500 MHz) automatically becomes the active frequencyon both COM radios.HAZARD DISPLAYS WITH LOSS OF GPS POSITIONIf GPS position is lost, or becomes invalid, selected hazards being displayed on theNavigation Map Page are removed until GPS position is again established.Loss of Hazard Functions with Loss of GPSPositionUNUSUAL ATTITUDESThe PFD ‘declutters’ when the aircraft enters an unusual attitude. Only the primaryfunctions are displayed in these situations.The following information is removed from the PFD (and corresponding softkeysare disabled) when the aircraft experiences unusual attitudes: