Garmin GNC 420 - Manual (Page 233)

GNC 420(A) Pilot’s Guide and Reference
SECTION 13 – MESSAGES,
ABBREVIATIONS, & NAV TERMS
13-5
Message Description
Invalid FPL
modification An attempt was made to modify the final course segment (FAF to MAP) of an instrument
approach. The GNC 420 does not allow the modifications.
Invalid waypoint ident
An attempt was made to create a user waypoint with an invalid name. The GNC 420 does
not allow spaces between characters in the waypoint name.
MAIN processor
requires service The GNC 420 has detected a failure in the main system processor. The GNC 420 is not
usable and should be taken to a Garmin dealer for service.
Memory battery low
The internal battery that sustains user memory is low and should be replaced by a Garmin
dealer as soon as possible. Failure to do so may result in loss of stored data, including flight
plans, user waypoints, unit settings, and satellite data.
Near airspace -- less
than 2 nm
The GPS-calculated position is within 2 nm of a special use airspace boundary, but the
aircraft is not projected to enter the airspace. This message is automatically disabled within
30 nm of an arrival airport, when an approach is loaded.
Need altitude - display
position page
The GPS receiver needs altitude input in order to start and/or continue 2D navigation. Select
the Position Page and verify the altitude reading. If the altitude is in error by more than
500 feet, enter the current altitude as accurately as possible. An inaccurate altitude directly
translates into inaccurate position information.
No altitude input is
being received
No altitude data is being received from RS-232 (Serializer: Icarus, Rosetta or Shadin) or grey
code inputs. If the problem persists, contact a Garmin dealer and check the installation
and installation settings. When this message occurs, no pilot action is required if enough
satellites are available for a 3D position fix (provided no RAIM warnings are present).
However, if only a 2D position fix is possible, the pilot should maintain the GPS altitude
within 1,000 feet of pressure altitude by entering the altitude on the Position Page.
No basemap data
available
The GNC 420 has detected a failure in the built-in basemap (land data) memory. Land data
does not appear on the Map Page. Other unit functions continue to work normally; however,
the GNC 420 should be taken to a Garmin dealer for service at the earliest convenience.
Not receiving input
data on 429 Channel 1 No data has been received on the ARINC 429 channel 1 connection for a period exceeding
five seconds. If the problem persists, the installation should be checked by a Garmin dealer.
Not receiving input
data on 429 Channel 2 No data has been received on the ARINC 429 channel 2 connection for a period exceeding
five seconds. If the problem persists, the installation should be checked by a Garmin dealer.
Not receiving input
data on 232 Channel 1 No data has been received on the RS-232 channel 1 connection for a period exceeding ten
seconds. If the problem persists, the installation should be checked by a Garmin dealer.
OBS key stuck
The OBS Key is stuck in the enabled (or pressed) state. Try pressing the OBS Key again to
cycle its operation. If the message persists, contact a Garmin dealer for assistance.
190-00140-20 Rev. K