I have been struggling with a custom board that contains the Teseo liv3F. When debugging the module with Teseo suite pro, i can see good signal levels from 3 GPS satellites but the Fix Mode is set to NO FIX and the Lat = Long = 0.
I have also started recently working with the Teseo and have encountered this behaviour when I trigger a cold start.
Alternatively I found a setting on in the software manual "CDB-ID 222 – LMS operating mode setting 1" where it looks like you can disable a 2D fix on the Teseo, which would mean that it probably requires 4 satellites at least to get a fix.
Get a better antenna/location, the signal strength is woeful, you won't be able to pull navigation data (ephemeris) at those levels. The alternative would be to get that data via a network, ie AGPS
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