In this article I listed some common problems I encountered when I tried to use Freematics OBD-reader together with traccar device-tracking server. Both are open-source, thanks to which I was able to improve both and their cooperation.
Freematics: official repo and my fork.
traccar: official repo and my fork.
- Currently, Freematics cannot switch between WiFi and SIM depending on connectivity. If you want to switch to a different WiFi or mobile operator - you need to open your bloody Windows and recompile everything :)
- Doesn't work at all without external power, has no battery. Works only when connected to USB (3.7V), OBD-II (12V), or SAE J1939 (24V). It me