Garmin G3X Pilot's Manual page 361

If Navigation Mode is active and either of the following occur, the AFCS
reverts to Roll Hold Mode (wings rolled level):
• Different VOR tuned while in VOR Navigation Mode (VOR Navigation
Mode reverts to armed)
• Active navigation source manually switched (with the CDI SRC
Softkey on the PFD/PFD Page, or the CDI Key on the external navigator)
• Active flight plan is deleted (only GPS-based modes)
• GPS reception is lost
If VOR Navigation Mode is active and the VOR signal is lost, the autopilot
reverts to Roll Hold Mode (wings rolled level) and reverts VOR Mode to armed
in the event the VOR signal is reestablished.
OBS MODE
In OBS Mode the Selected Course is controlled using the OBS CRS Softkey.
Or press XPDR/CRS > OBS CRS when a transponder is configured and turn
the FMS Joystick.
Enabling/disabling OBS Mode (without external GPS navigator):
1) From the Active Flight Plan Page, press the MENU Key while navigating a
flight plan or Direct-to.
2) With 'Set OBS and Hold' highlighted, press the ENT Key. The OBS Mode
Box is highlighted.
3) Turn the FMS Joystick to select the desired course to/from the waypoint.
4) To cancel OBS Mode and return to automatic waypoint sequencing, press
the MENU Key, with 'Release Hold' highlighted, press the ENT Key.
Enabling/disabling OBS Mode (with external GPS navigator config-
ured):
1) EXTERNAL NAVIGATOR: Press the OBS Key. The 'Set OBS and Hold' Active
Flight Plan Page menu option is now available.
2) G3X: Turn the FMS Joystick to select the desired course to/from the
waypoint.
190-01115-00 Rev. K Garmin G3X Pilot's Guide
AFCS
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