Garmin APOLLO GX SERIES Service Manual - page 124
Garmin AT
Rev --
9-2
GX Service Manual
© 2004 Garmin AT
ERROR MESSAGE
CAUSE
ACTION
Altitude encoder
communications failure
1. Altitude encoder unit
2. Wiring between units
3. NAV
board
1. Check
altitude
encoder.
2. Check wiring from encoder to GX.
3. Replace the NAV board. (See NAV
Board Replacement procedure.)
Fuel/Air Data
Communications Failure
1. Fuel/air
data
unit
2. Wiring between units
3. NAV
board
1. Check fuel/air data unit.
2. Check wiring from F/ADC to GX.
3. Replace the NAV board. (See NAV
Board Replacement procedure.)
Memory Failure; User
Setups Have Been Reset
(repeats on every startup)
1. Software
2. NAV
board
1. Initialize unit. (See Complete
Initialization procedure).
2. Upgrade software to v 2.2.
3. Replace the NAV board. (See NAV
Board Replacement procedure.)
Low Battery Voltage: Unit
Needs Service
1. Low
battery
voltage
2. Fracture
between
solder fillet and leads
on battery holder
3. NAV
board
1. Check battery voltage. Replace if
below 2.75V. (See Battery
Replacement procedure.)
2. Replace the NAV board. (See NAV
Board Replacement procedure.)
Internal Battery Failure:
Turn off Unit/Needs Srvc!
NAV board
Replace the NAV board. (See NAV
Board Replacement procedure.)
COM Radio FAILURE!
Service Now
1. No
connection
between boards
2. No radio power (blown
fuse)
3. Comm
board
4. NAV
board
1. Verify 8-pin NAV to Comm
connector (Comm J4 - NAV J606).
2. Verify A/C power at F400. Replace
fuse if blown (See Comm Board
Fuse Replacement procedure).
3. Replace Comm board. (See Comm
Board Replacement procedure.)
4. Replace the NAV board. (See NAV
Board Replacement procedure.)
Software Test Failed:
Contact UPS Aviation
Technologies
User Database Memory
Failure…
Flight Plan Memory
Failure…
Memory Test Failure…
NAV board
1. Initialize unit. (See Complete
Initialization procedure).
2. Replace the NAV board. (See NAV
Board Replacement procedure.)