(2011) Service Advisory 1138 Rev A: GTN 625/GTN 635/GTN 650/GTN 725/GTN 750 Units and ‘Data Source’ Error Messages

AFFECTED PRODUCTS

GTN 6XX/7XX Units with Main Software Version 2.00.

DESCRIPTION

When the GTN inputs are configured for certain traffic or altitude formats, one or both of the following messages may be displayed:

    ‘DATA SOURCE – Heading source inoperative or connection to GTN lost’

    ‘DATA SOURCE – Pressure altitude source inoperative or connection to GTN lost’

This message will persist throughout the power cycle. Once viewed, it stops blinking. For aircraft in which a heading source or pressure altitude source is not connected to the GTN, the message(s) are nuisance messages only. For aircraft in which a heading source or pressure altitude source is connected to the GTN, the message(s) function correctly, appearing only if the GTN is not receiving heading or pressure altitude information.

PILOT ACTION

No pilot action is necessary.

RESOLUTION

Garmin plans to correct this issue in software version 3.00.