Garmin GTN 650 Series Pilot's Manual Upgrade Supplement page 108

Message
COM RADIO -
Com radio needs
service.
COM RADIO -
Com radio may be
inoperative.
COM RADIO -
Com overtemp
or undervoltage.
Reducing
transmitter power.
COM RADIO -
Com locked to
121.5 MHz. Hold
remote com
transfer key to exit.
CONFIGURATION
- Terrain/TAWS
configuration is
invalid. GTN needs
service.
CONFIGURATION
MODULE -
GTN configuration
module needs
service.
102
GTN 650/750 Series SW V3.00 Upgrade Supplement 190- 01007-05 Rev A
Description
The com radio is
reporting that it needs
service. The com radio
may continue to
function.
The com radio is not
communicating properly
with the system.
Com radio is
in overtemp or
undervoltage mode
and transmitting power
has been reduced to
prevent damage to the
com radio. Radio range
will be reduced.
Com radio is locked to
121.5 MHz.
TAWS is inoperative
due to a configuration
problem with the GTN.
This message will be
accompanied by a TER
FAIL annunciation.
The GTN cannot
communicate with its
configuration module.
The GTN may still have
a valid configuration.
Action
Cycle the power to the COM radio.
Contact dealer for service.
Press and hold the volume knob or
the external com remote transfer
(COM RMT XFR) switch, if installed
– this will force the com radio to
121.5 MHz. Contact dealer for
service.
Decrease length of com
transmissions, decrease cabin
temperature and increase cabin
airflow (especially near the GTN).
Check aircraft voltage and reduce
electrical load as necessary.
Contact dealer for service if this
message persists.
The external com remote transfer
(COM RMT XFR) switch has been
held and the com radio is tuned to
121.5. To exit this mode, hold the
com remote transfer (COM RMT
XFR) switch for two seconds.
Contact dealer for service.
Contact dealer for service.