I have a problem with FMB920 locators. Sometimes it wakes up from "deep sleep" but fails to catch the GPS signal. This occurs quite rarely but in different devices. Only sent SMS with the command "cpureset" helps.
During this time, it normally recognizes driving through the accelerometer, sends data frequently as normal while driving, but the number of satellites are zero. The status of the GNSS receiver is "on without fix". The position is sent which was last memorized.
The configuration of these locators is quite similar. I use deep sleep after 70 minutes of inactivity (stop). Most often in the morning after night the FMB920 is woken up by the accelerometer and it happens that the GPS does not catch the fix (I can see the status of the GNSS receiver in the sent data).
Their firmware is rather the latest because they were purchased within the last six months. I can provide their configuration so that you can recreate it in your tests.
