190-02246-11
GI 275 Part 23 AML STC Maintenance Manual
Rev. 1
Page 4-25
Figure 4-18 ADC Alert Message Troubleshooting
ADC Fault Messages
If fault persists,
contact Garmin.
ADC <1/2/3>
MISSING
-or-
ADC MISSING
Cause
Multiple ADCs are
configured in the
system and the
reported ADC is not
detected
Corrective
Action
Ensure the missing
ADC is powered
Ensure the missing
ADC configuration
is correct
Verify wiring is
correct
ADC <1/2/3>
MISCOMPARE
-or- ADC
MISCOMPARE
Cause
Multiple ADCs are configured, a
reported ADC pressure altitude
difference of 200ft or more is
detected
Maintenance
Log Message
Maintenance
Log Message
ADC <1/2/3> does not
match other senosrs
All ADC sensors do not
match
ADC <1/2/3> data is
missing and cannot be
compared
Not enough ADC sensors to
perform a comparison
Multiple ADCs are configured, a
reported ADC airspeed
difference of 7kts or more is
detected
Corrective
Action
Ensure the altitude
and airspeed units
of measure are the
same for all
configured ADCs
Ensure there are no
leaks in the pitot
static system
ADC <1/2/3>
reports service
required
Cause
Corrective
Action
ADC <1/2/3>
reports service
required
Maintenance
Log Message
ADC <1/2/3>
reports
configuration error
Cause
ADC is reporting a
configuration error
Corrective
Action
Verify ADC
configuration
settings
Service required
Cause
Maintenance
Log Message
Corrective
Action
<AHRS>
configuration does
not match what the
unit expected
AHRS LRU is not
configured correctly
Verify AHRS
configuration
settings
ADC internal
calibration
mismatch
Perform ADC
calibration
procedure
