Garmin G1000 NXi Pilot's Manual page 373

Changing the VNV Target Altitude
Pressing the CWS Switch while in VNV Target Altitude Capture Mode does not cancel the mode.
NOTE:
Changing the current VNV Target Altitude while VNV Target Altitude Capture Mode is active causes
the flight director to revert to Pitch Hold Mode. Vertical Path Tracking and the appropriate altitude
capture mode are armed in preparation to capture the new VNV Target Altitude or the Selected Altitude,
depending on which altitude is to be intercepted first.
VNV target altitudes can be changed while editing the active flight plan (see the Flight Management
Section for details).
190-02177-00 Rev. A
Altitude Reference (In This Case,
Equal To VNV Altitude Target)
Flash up to 10 sec, Indicating Automatic Transition
Figure 7-18 Automatic Mode Transitions During Altitude Capture
Garmin G1000 NXi Pilot's Guide for the Cessna Nav III
AUTOMATIC FLIGHT CONTROL SYSTEM
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