I am not much into this, but I believe that to be really useful the OBD-II PIDs (generic): https://en.wikipedia.org/wiki/OBD-II_PIDs https://en.wikipedia.org/w

I am not much into this, but I believe that to be really useful the OBD-II PIDs (generic): https://en.wikipedia.org/wiki/OBD-II_PIDs https://en.wikipedia.org/wiki/OBD-II_PIDs should be integrated with the ones by the given manufacturer on the specific model, and AFAIK all the money is in the software that can read those non-standard PID's. And this is border-line (or downright just over the border) with hacking and/or reverse engineering the manufacturer's own software.