Garmin GNC 420W Pilots Guide - Page 233

SECTION 13 - MESSAGES, ABBREVIATIONS, & NAV TERMS 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. The GPS receiver needs altitude input in order to start and/or continue 2D navigation. Select Need altitude - display the Position Page and verify the altitude reading. If the altitude is in error by more than position page 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 No data has been received on the ARINC 429 channel 1 connection for a period exceeding data on 429 Channel 1 five seconds. If the problem persists, the installation should be checked by a Garmin dealer. Not receiving input No data has been received on the ARINC 429 channel 2 connection for a period exceeding data on 429 Channel 2 five seconds. If the problem persists, the installation should be checked by a Garmin dealer. Not receiving input No data has been received on the RS-232 channel 1 connection for a period exceeding ten data on 232 Channel 1 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 GNC 420(A) Pilot's Guide and Reference 13-5