Garmin G500, Pilot'S Manual, Page: 80 / 440

1-52 Pilot’s Guide 190-01717-10 Rev. H
System Description
<GDU> demo
mode, do not use in
flight.
The unit is in
demonstration mode.
To exit demo mode:
Cycle power to the GDU. If
the problem persists, contact
dealer for service.
Operating the GDU in demo
mode during flight is
prohibited.
GPS 1/2 inoperative.
The indicated GPS
source failed.
Ensure that the navigator(s) is
on and receiving a GPS
signal.
Switch to an alternate
navigation source.
Contact dealer for service.
Communication with the
indicated GPS is lost.
NAV 1/2
inoperative.
The indicated NAV
source is failed, or input
data is not received.
Switch to an alternate
navigation source.
<LRU> reports
service required.
The indicated LRU
reports an internal fault
and requires service.
Appears only when the
aircraft is on ground.
Contact dealer for service.
Reset altitude
preselector to
enable VPATH
descent.
TOD ahead.
Vertical deviation is
available and the
selected altitude is
< 75 ft below current
altitude.
Appears only for aircraft
equipped with GFC 600.
Lower the selected altitude to
at least 75 ft below the
current aircraft altitude.
<GDU> backlight
calibration lost.
The GDU cannot read
LED calibration data, or
the data is corrupt.
Sunlight readability may
be degraded.
Appears only when the
aircraft is on ground.
Contact dealer for service.
<GDU> controller
unavailable.
Communication with
GCU 485 is lost. Appears
only when the aircraft is
on ground.
Operate the indicated GDU
using the touchscreen
controls.
ADVISORY CONDITION CORRECTIVE ACTION