From my understanding, OBD II does not directly tell if a car is in forward or reverse gear. I wonder what the best way to derive such information from OBD data if there is any.
Following the discussion in this post, specifically I would like to know if PID62 says forward when it is positive and reverse when it is negative. If not, is there any other other PID can reveal forward/reverse information with a foolproof mapping logic. If any, please specify the PID and the mapping logic.