GTN 6XX/7XX series navigators with software version 6.00 and later are affected.
GTN software version 6.00 and later provide an improved methodology for computing GPS steering and navigation paths. This improvement makes the GTN consistent with the Garmin Integrated Flight Decks and complies with the requirements of DO-229D. This change provides improved path definition on the moving map and provides Course Deviation Indicator (CDI) guidance during the transition between flight plan legs.
This is a change from previous versions of the GTN. GTN users need to be aware of how these changes affect the display of navigation on the GTN and on externally interfaced HSIs and CDIs.
See Service Advisory 1619 for details.