Garmin GTN 725 Cockpit Reference Manual page 70

Message
DATALINK-
GDL 88 control panel
input fault. Check
transponder is in correct
mode.
DATALINK-
GDL 88 ADS-B fault.
Pressure altitude
source inoperative or
connection lost.
DATALINK-
GDL 88 ADS-B traffic
has failed.
DATALINK-
GDL 88 CSA failure.
DATALINK-
GDL 88 external traffic
system inoperative or
connection lost.
DATALINK-
GDL 88 external traffic
system has a low
battery.
DATALINK-
GDL 88 configuration
module needs service.
DATALINK-
GDL 88 needs service.
62
Description
The GDL 88 has lost
communication with the
transponder.
The GDL 88 has lost
communication with the
pressure altitude source.
GDL 88 may have lost
GPS position.
The GDL 88 has detected
an internal failure.
The GDL 88 is reporting
to the GTN that the CSA
application has failed.
Traffic alerting on ADS-B
traffic is unavailable.
The GDL 88 has detected
a TAS/TCAS input fault.
The GDL 88 is reporting
that the external traffic
system has a low battery.
The GDL 88 has detected
a configuration module
fault.
GDL 88 has detected an
internal fault.
GTN 725/750 Cockpit Reference Guide (CRG)
Action
Contact dealer for service.
Contact dealer for service.
Contact dealer for service.
Ensure the aircraft has a
clear view of the sky. If the
problem persists, contact
dealer for service.
Contact dealer for service.
Contact dealer for service.
Contact dealer for service.
Contact dealer for service.
190-01007-04 Rev. D