There are a ton of free programs. Most are code readers with some basic pid displays like engine temp o2 voltage and stuff like that. i used to use one called Digimoto lite for just basic stuff. None of the cheapos do any b- directional testing or air bag or abs.
A friend of mine has scan Xl which does do some airbag and ABS but it is not free.
Artificial Intelligence is no match for Natural Stupidity