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190-02207-A2
GPS 175/GNX 375/GNC 355 Part 23 AML STC Maintenance Manual
Rev. 3
Page 5-13
Figure 5-6 XPDR Alert Troubleshooting
Sheet 2 of 5
GNX 375 XPDR Alert
Messages
If fault still exists,
contact Garmin.
Transmit Monitor
Failure
Transponder
FPGA Failure
- 1090MHz
transmission
failures,
- Internal hardware
problem
- Wiring problem
- Incompatible
antenna
FPGA software did
not load properly
Reload software
Reset config and
reconfigure unit
Verify antenna,
connections, and
coax installation
Inspect wiring and
connections
Reload software
Reset config and
Reconfigure unit
Verify antenna,
connections, and
coax installation
Inspect wiring and
connections
Transponder
Or
1090 ADS-B
Out
Transponder
Or
1090 ADS-B
Out
Failure
Failure
Cause
Cause
Corrective
Action
Corrective
Action
Maximum
Temperature
Exceeded
Minimum
Temperature
Exceeded
Low Temperature
Failure
High
Temperature
Failure
Internal
Temperature has
exceeded limits.
Possible internal
damage may have
occured
Internal
Temperature has
exceeded limits.
Possible internal
damage may have
occured
Failure
Failure
Cause
Cause
Corrective
Action
Corrective
Action
Transponder
FPGA ROM
Failure
FPGA software
load issue
Reload software
Transponder
Or
1090 ADS-B
Out
Failure
Cause
Corrective
Action
Transponder
ROM Failure
Software load
issue
Reload software
Transponder
Or
1090 ADS-B
Out
Failure
Cause
Corrective
Action
Reset config and
Reconfigure unit
Reset config and
Reconfigure unit
Transponder
Calibration
Failure
Factory
transponder
calibration data
invalid
Reload software
Reset config and
reconfigure unit
Verify transponder
antenna,
connections, and
coax installaiton
Inspect wiring and
connections
Transponder
Or
1090 ADS-B
Out
Failure
Cause
Corrective
Action
Transponder
Configuration
Failure
Transponder
configuration data
is invalid or
incomplete
Reload software
Reset config and
reconfigure unit
Transponder
Or
1090 ADS-B
Out
Failure
Cause
Corrective
Action
Transponder
Electrical Failure
Internal voltage
mis-compare with
the unit
Reload software
Reset config and
reconfigure unit
Verify all wiring,
shorts/opens.
Verify power and
ground
connections
Transponder
Or
1090 ADS-B
Out
Failure
Cause
Corrective
Action
Bring the GNX 375
within operating
temperature as
described in the
Temperature
diagnostics page.
See Section
3.4.4.13.
Bring the GNX 375
within operating
temperature as
described in the
Temperature
diagnostics page.
See Section
3.4.4.13.