You can run this script as root: https://source.puri.sm/angus.ainslie/librem5-agps/-/blob/main/usr/bin/gnss-test
After a few seconds you should see “timestamp” with current time in UTC. Leave it with a good view of the sky for about 15 minutes and check whether it acquired a fix.
Ok, I’ll test. Should all apps be closed and WiFi killed with the switch?
You may want to close any kind of GPS apps to not interfere, but otherwise - it’s up to you.
GPS 0.4
--------------------------------------
longitude 113.85258300
latitude 22.65956600
altitude (m) 84.90
accuracy 99.0
fix None
View sats
Solution sats
timestamp 2023-02-25 09:04:39.82
Fix time 1677312279.000
TTFF 0.0
It says no fix, but it gives me lat and longitude.
Your experience look rather similar to mine. I never got a reliable GPS fix. Here a description of some of my experiments: Librem 5 GPS/Location Tracking.
If you don’t get a fix even after 25 minutes of leaving it outside with good sky coverage with this script running, then please contact support - older phones may need a small hardware fix in order to improve GPS sensitivity; this may also happen if the antenna ground pin in the case is not making proper contact. Support should be able to guide you.
Thanks @dos. Yes, I contacted support. They responded quickly. See: Librem 5 GPS/Location Tracking and Librem 5 GPS/Location Tracking. I still did not dare to apply the fix myself. But now I read about GPS working better for others, I might try a fresh image and maybe apply the hardware fix, if still needed.
Ok, it has been 30 minutes now and no fix, so I may have to do that or can I try the steps lined out in the topic by @janvlug ? I have to work up the guts to do it, though.
How do I quit the script?
i was going to say the GPS aboard the L5 is crap. Because, after doing the (succesful) initialization described above, I hoped the L5 could guide me home from work. And it didn’t. At least not for the first 15 or 20 minutes. The GPS, at first, decided I was still at the spot where it initialized earlier, while in actual fact I was a couple of kilometers closer to home. Then it jumped to a completely different city in the Netherlands - nowhere close to either my home or my work. Then it reverted to my place of work, and only after I stopped and rebooted,and waited for another couple of minutes it settled on my actual location. From then on everything was very accurate - and I mean really very accurate, to within a yard or two.
I don’t think the reboot.mattered much, but I am afraid this wasn’t the last time I had ‘initialize’ the GPS. And eventhough the L5 guided me home very accurately, it still shows me being a good hundred meters away from my home every time I start Pure Maps from my home.
So, yes the navgation seems useable (at least while walking on biking), but not without its hickups.
Press (several times after each other) Ctrl-C in the terminal where you started it.
This simply sounds like it took it a few minutes to obtain a fix and it used other less accurate sources of location instead meanwhile.
I am not sure what is happenjng. I don’t think the wifi has anything to do with it, though. The postion keeps jumping from somewhere within ten meters of my house, to a ‘preferred’ spot around a hundred meters from my house, to some other spots a couple of kilometers from the house, to some location around eighty kilometers South of my actual location. In the end, it settles on the preferred spot - which isin a swiming pool, by the way.
It make no derence whether the wifi is on or off.
That sounds exactly like jumping between various sources, one of them possibly being completely outdated GPS position stored in the module and the other inferred from GSM cells, WiFi access points or GeoIP. That’s why it’s important to check things directly at the GPS module, as looking at position on map apps just doesn’t give you enough information to know what’s going on.
I noticed this in the changes for geoclue 2.7.0: “Location description now contains information about its source”.
The latter might be the case (though not the wifi access points), but the first definitely not: the phone points to place it has never been (like the one 80 km outside Amsterdam).
Like for me, China.
But it has been in China! 
(Unless you bought the L5USA, and even then, some parts may have been there.)
Yes, as I stated above at least parts of it! 
Thanks for the pointer to a configuration issue:
/etc/geoclue/geoclue.conf
Changing the [modem-gps] source to =false stopped the Modem Manager from eating up 70-100% CPU, with 4G on, WiFi on, geoclue running, Gnome maps running, and geoconfiguration with NMEA, 3G, CDMA, WiFi source =enabled.
Make sure to sudo systemctl restart geoclue.service after changing the .conf file otherwise settings wont come in effect until phone restart.