[go37pi]

The control protocols are not well documented at all, starting in 1996, all cars are required to have OBD ports.

The manufacturers don't want people to know the control protocols for various reasons (security, manufacturers make money selling repair materials and codes to repair shops, licensing codes to third parties etc.)

But it is possible to discover the control protocols, a friend and I worked on it for his Toyota Yaris I think by monitoring all the outputs from the OBD and changing a status (locking a door) and watching what bits change. We got a lot of equipment and help from a professor at school. We used a GPS and ended up making a little app that monitored where the car went, its speed, and various car statuses on google maps. There's a lot of info out on the Toyota Prius if you feel like getting started.