(2022) Service Advisory 20109 Rev D: Erroneous GPS position and momentary false TAWS alerts

REVISION D:

Added GPS 175/GNX™ 375/GNC® 355 and GTN Xi Resolution

PRODUCTS AFFECTED:

All SBAS-enabled Garmin Integrated Flight Decks (G900X, G950, G1000(H) G1000(H) NXi, Cirrus PerspectiveTM, Embraer ProdigyTM, G2000, G3000, G5000, and Embraer Prodigy® Touch systems), GTN Xi Series, GPS 175, GNX 375, GNC 355, GNS 400W/500W Series, GNS 480, GTN 6XX/7XX Series products operating within the area depicted below are affected.

ISSUE:

Affected Garmin equipment may periodically experience GPS position errors for approximately six seconds, and momentary TAWS false alerts when utilizing corrections from the Japanese MSAS (MTSAT Satellite Augmentation System) space-based augmentation system.

ACTION:

Disable MSAS.

NOTE
Refer to the applicable pilot’s guide for instructions on how to disable MSAS.

RESOLUTION:

MSAS will be disabled automatically in the November 2020 aviation database cycle. A future software and database update will address the issue and re-enable the use of MSAS in the affected products.

For GTN 6XX/7XX products this has been fixed in GTN 6XX/7XX GPS/WAAS Software Version 8.3. GTN 6XX/7XX GPS/WAAS Software Version 8.3 is packaged with GTN 6XX/7XX Main Software Version 6.72.

For GPS 175/GNX™ 375/GNC® 355 products this has been fixed in GPS 175/GNX™ 375/GNC® 355 GPS/WAAS Software Version 8.2.

For GTN Xi products this has been fixed in GTN Xi GPS/WAAS Software Version 8.2.