Garmin G1000 Cockpit Reference Guide for the Cessna Citation Mustang190-00600-04 Rev. A 87Annunciations & AlertsFlightInstruments EICASNav/Com/XPDR/Audio AFCS GPS NavFlightPlanning ProceduresHazardAvoidanceAdditionalFeaturesAbnormalOperationAnnun/Alerts Appendix IndexGRS 77 MESSAGE ADVISORIESMessage CommentsAHRS1 TAS – AHRS1 not receivingvalid airspeed.The #1 AHRS is not receiving true airspeed fromthe air data computer. The AHRS relies on GPSinformation to augment the lack of airspeed.The system should be serviced.AHRS2 TAS – AHRS2 not receivingvalid airspeed.The #2 AHRS is not receiving true airspeed fromthe air data computer. The AHRS relies on GPSinformation to augment the lack of airspeed.The system should be serviced.AHRS1 GPS – AHRS1 using backupGPS source.The #1 AHRS is using the backup GPS path.Primary GPS path has failed. The system shouldbe serviced when possible.AHRS2 GPS – AHRS2 using backupGPS source.The #2 AHRS is using the backup GPS path.Primary GPS path has failed. The system shouldbe serviced when possible.AHRS1 GPS – AHRS1 not receivingany GPS information.The #1 AHRS is not receiving any or any usefulGPS information. Check AFMS limitations. Thesystem should be serviced.AHRS2 GPS – AHRS2 not receivingany GPS information.The #2 AHRS is not receiving any or any usefulGPS information. Check AFMS limitations. Thesystem should be serviced.AHRS1 GPS – AHRS1 not receivingbackup GPS information.The #1 AHRS is not receiving backup GPSinformation. The system should be serviced.AHRS2 GPS – AHRS2 not receivingbackup GPS information.The #2 AHRS is not receiving backup GPSinformation. The system should be serviced.AHRS1 GPS – AHRS1 operatingexclusively in no-GPS mode.The #1 AHRS is operating exclusively in no-GPSmode. The system should be serviced.AHRS2 GPS – AHRS2 operatingexclusively in no-GPS mode.The #2 AHRS is operating exclusively in no-GPSmode. The system should be serviced.AHRS MAG DB – AHRS magneticmodel database version mismatch.The #1 AHRS and #2 AHRS magnetic modeldatabase versions do not match.