TranslationThe receiver otherwise works perfectly: it gets a fast, stable GPS fix, navigation is normal, and GPS/EGNOS satellites show solid, high-contrast signal bars. However, with **GPS + GLONASS enabled**, the GLONASS satellites never seem to become active or contribute to the fix.
The attached photos show the problem clearly: for example, GPS 19 has a normal dark/solid bar, while GLONASS 67 and 73 only have very pale grey bars.
What I have tried:
- Left the unit outside under completely open sky for an entire evening. No change.
- Repeated **Reset All Settings** and **Delete All/User Data** from the menus several times.
- Performed the hardware/master reset using **PAGE + ENTER + POWER**, then confirmed “Erase all user data”.
- Used **Auto Locate**.
- Switched to **Demo Mode**, then back to **Use Satellite System**.
- After some boots, only GPS satellites appear initially. Demo Mode → Use Satellite System → Auto Locate makes the GLONASS columns appear, but they remain pale and unused.
- Downgraded from firmware **6.60 to 5.90**, then further down to **5.50**, and afterwards upgraded to **5.60**. GLONASS behaved exactly the same on every tested version.
- Connected through Garmin Spanner/GpsGate and checked the NMEA output. GLONASS satellite IDs are reported as visible, but they are not used in the position solution.
- Backed up the complete Garmin directory and tested deleting the GNSS data files:
Code: Select all
/Garmin/GPS/ARC.BIN /Garmin/GPS/BEE.BIN /Garmin/GPS/MT.NVM
- I also deleted the entire `/Garmin/GPS/` directory and rebooted. No improvement.
- There was no `EPO.BIN` or `RemoteSW` directory in the original backup.
* Garmin GPSMAP 64s
* Original/current main firmware: 6.60
* Tested firmware versions: 5.50, 5.60, 5.90 and 6.60
* PCB: GPSMAP 64 S V7
* Part number: 006-B1859-00
Has anyone seen this exact behaviour on a GPSMAP 64s? Is there another Garmin-specific GNSS reset/reflash procedure I have missed, or does this point to a receiver hardware fault?
Thank you!
