190-00734-11
GTX 33X and GTX 3X5 ADS-B Maintenance Manual
Rev. 6
Page 5-4
Figure 5-3 GTX 33/33D Transponder Failure/Fault Messages
Verify ADS-B TX is on
and GPS source is
receiving valid GPS
position data
Verify GPS source
configuration is IAW
the Installation
Guidance
GTX 33 Failure
Messages
TRANSPONDER 1 –
ADSB is not
transmitting position
TRANSPONDER 2 –
ADSB is not
transmitting position
Verify the aircraft has a
clear view of the sky
The transponder has
insufficient data to
support ADS-B Out
transmission
Cause
The transponders are
configured for different
Mode S addresses
Corrective
Action
Corrective
Action
If fault still exists,
return to Garmin.
TRANSPONDER –
Transponder 1 and 2
Mode S addresses do
not match
Cause
The transponder is
reporting a system
failure
Corrective
Action
TRANSPONDER 1 –
Transponder 1 needs
service
Cause
The transponder is
reporting a system
failure
Corrective
Action
TRANSPONDER 2 –
Transponder 2 needs
service
Verify the Mode S
address for each
transponder and that
they match.
Cause
Verify RS-232 wiring
between GTN/GNS
and GTX
Check configuration of
GTX and GTN/GNS
TRANSPONDER 1 –
Transponder 1 is
inoperative or
connection to GTN/
GNS is lost
TRANSPONDER 2 –
Transponder 2 is
inoperative or
connection to GTN/
GNS is lost
If two transponders are
installed, ensure both
units are powered on
The GTN/GNS cannot
communicate with the
transponder or the
transponder is
reporting a system
failure
Corrective
Action
Cause
Cause
Cause
The GTN cannot
communicate with the
transponder or the
transponder is
reporting a system
failure
If two transponders are
installed, ensure both
units are powered on
Check configuration of
GTX and GTN/GNS
Verify RS-232 wiring
between GTN/GNS
and GTX
The transponder has
insufficient data to
support ADS-B Out
transmission
Corrective
Action
Corrective
Action
Verify ADS-B TX is on
and GPS source is
receiving valid GPS
position data
Verify GPS source
configuration is IAW
the Installation
Guidance
Verify the aircraft has a
clear view of the sky
Check configuration of
GTX and GTN/GNS
Check configuration of
GTX and GTN/GNS
Re-install the latest
software
Re-configure the GTX
Re-install the latest
software
Re-configure the GTX