Chevrolet Corvette 2012 Manual page 77

Press NAV to access the map
screen. Press the MENU
touch-screen button on the map
screen.
All of the navigation system features
can be accessed from this screen.
The navigation system determines
the position of your vehicle by using
satellite signals, various vehicle
signals, and map data.
At times, other interferences such
as the satellite condition, road
configuration, the condition of the
vehicle and/or other circumstances
can interfere with the navigation
system's ability to determine the
accurate position of the vehicle.
The GPS shows the current position
of your vehicle using signals sent by
the GPS Satellites of the United
States Department of Defense.
When your vehicle is not receiving
signals from the satellites, a symbol
appears on the map screen. Refer
to
This system may not be available or
interferences may occur if any of the
following are true:
Signals are obstructed by tall
buildings, trees, large trucks,
or a tunnel.
Objects are located on the rear
shelf of the vehicle.
Satellites are being repaired or
improved.
After-market glass tinting has
been applied to the vehicle's
rear windshield.
.