Garmin G500 Instructions Manual page 315

3.2.2 GPS Data Failure
GPS data failure may be indicated by any or all of following:

Loss of GPS course deviation information on HSI

Amber "LOI" text on the HSI

Amber "NO GPS POSITION" text on the MFD moving map

Loss of waypoint bearing or distance information
Select alternate GPS source, if available, by pressing "1-2" softkey on
1.
PFD.
If alternate GPS source is not available:
Select alternate navigation source using "CDI," "1-2," or "BRG"
2.
softkeys on PFD, or refer directly to external navigation data.
3.2.3 Navigation Data Failure (VOR/LOC/GS/ADF)
Navigation data failure may be indicated by any or all of following:

Loss of course deviation information on HSI

Loss of glideslope/glidepath information on PFD

Loss of bearing pointer on HSI
Select alternate navigation source using "CDI," "1-2," or "BRG"
1.
softkeys on PFD, or refer directly to external navigation data.
3.2.4 Synthetic Vision (SVT) Failure
Several data sources are required to display SVT on the PFD (GPS, terrain
database, attitude information, etc.). If any of these required data sources
become unreliable or unavailable, SVT will automatically be removed, and the
PFD will revert to the standard display of blue sky over brown ground. If there is
a discrepancy between the SVT display and the actual terrain around the aircraft,
SVT should be turned off manually.
To turn off SVT:
Press the "PFD" softkey on the PFD.
1.
Press the "SYN VIS" softkey to turn off SVT.
2.
AFMS, GARMIN G500/G600 SYSTEM
FAA APPROVED
190-00601-01 Rev. L
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