EGPWS LINE MAINTENANCE MANUAL
CAGE CODE: 97896
SCALE: NONE SIZE: A
DWG NO.: 060-4199-180
REV: G
SHEET 28 of 68
TABLE 3-3: CURRENT FAULTS - EXTERNAL (EXAMPLES)
FAULT EXAMPLE
REASON
ARINC 429 Bus Fault
GPS BUS 1 INACTIVE
No expected input labels received for more
than 4 seconds
ARINC 429 Signal
Fault
ILS BUS 1 GLIDESLOPE FAULT FW
The SSM of the input data indicates
Failure/Warning
Note: Only the RS232 present Status will
report the ‘FW” part of the fault.
ARINC 429 Signal
Fault
ILS BUS 1 GLIDESLOPE FAULT UPD
The input label is not meeting the required
update rate.
Note: Only the RS232 present Status will
report the ‘UPD” part of the fault.
Analog Signal Fault
RADIO ALTIMETER 1 WIRING
FAULT
Open wire monitoring has detected no
connection.
AOA UNREASONABLE FAULT
AOA is not within 4 degrees of waterline
during takeoff roll (60-90 knots). Incorrect
Aircraft Configuration or AOA potentiometer is
Worn.
Discrete Input Faults
FLAP SWITCH FAULT
Indicates Landing Flaps for > 60 seconds with
an airspeed > 250 knots, or indicates Not
Landing Flaps for more than 2 seconds with
“Too Low Flaps” message below 100 feet.
GEAR SWITCH FAULT
Indicates Landing Gear for > 60 seconds with
an airspeed > 290 knots, or indicates Not
Landing Gear for more than 2 seconds with
“Too Low Gear” message below 100 feet.
AUDIO CANCEL INVALID
Discrete selected for > 30 seconds.
TERRAIN INHIBIT INVALID
Discrete selected for > 60 seconds.
GPWS INHIBIT INVALID
Discrete selected for > 60 seconds.
ALL MODES INHIBIT INVALID
Discrete configured to suppress both audio
and visual outputs and selected for > 60
seconds.
Or if aircraft type is configured for ‘Audio
Inhibit Monitoring’ then activation for > 60
seconds to inhibit only audio will cause this
fault.
GLIDESLOPE CANCEL INVALID
Discrete selected for > 15 seconds.
ILS SELECT INVALID
More than 1 discrete selected for > 5
seconds.
FLAP ANGLE UNREASONABLE
Invalid combination selected for > 30
seconds.
RANGE UNREASONABLE
No valid range provided for > 5 seconds.
SELF-TEST INVALID
Discrete selected for > 60 seconds.
AIR GROUND INVALID
Indicates On-Ground for > 60 seconds with an
airspeed > 290 knots.
MOMENTARY TERRAIN
SELECT 1 (or 2) INVALID
Selected for > 15 seconds.