Garmin aera 660 products with main software 3.20 (and earlier), D2 Bravo with GPS software version 3.10, (and earlier), and D2 Charlie with GPS software version 4.30 (and earlier) are affected.
To check the D2 Bravo and Charlie GPS software version go to the About page (Settings->System->About) and scroll down to display the GPS software.
The aera 660 main software version can be viewed below the Garmin logo on the power up screen.
The aera 660 and D2 Bravo/Charlie may not be able to acquire a 3-D GPS position fix and/or exhibit degraded GPS performance.
Connect the device to a wifi signal and download the latest unit software. For instructions on loading the latest software refer to the Garmin aera 660 Pilot’s Guide (190-02017-20), D2 Bravo Owner’s Manual (190-01674-00), and/or D2 Charlie Owner’s Manual (190-02236-00). All manuals can be found on www.garmin.com.
The area 660 software can also be downloaded from the Garmin website (https://buy.garmin.com/en-US/US/p/520775).
This issue has been fixed in D2 Bravo GPS software version 3.30, D2 Charlie GPS software version 4.40, and aera 660 main software version 3.30.