Garmin G3X Pilot's Manual page 147

Pressing the IDENT Softkey initiates the ident function and reverts to the top-level
softkeys.
With a remote transponder configured, the #2 PFD Softkey becomes XPDR (if
a navigation source is not selected) or XPDR/CRS (when the pilot can control the
navigation course).
IDENT
STBY / GND
IDENT
IDENT
CRS (subdued)
or
190-01115-00 Rev. K
Transponder
Transponder Data Box (Split-Screen)
XPDR
or
XPDR/CRS
OBS CRS
or
VOR CRS
or
LOC CRS
or
CRS CODE
ON ALT
CODE
Sends a distinct identity indication to Air Traffic Control
(ATC).
A navigation source is not selected
Garmin G3X Pilot's Guide
Code
Mode
MODE BACK
SET ID BACK
VFR BACK
CNS Interface
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Status
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