Firmware design for OBD2 - available PIDs request to ECU
@Lundin Sorry for the comment disguised as a answer, but I do not have the rep for a comment.
I'm sorry but the OP's usage of PID goes back to at least 1996 with the standardization of the On-board diagnositics port(OBD-II).  PID in this case stands for Parameter ID and as such is used by all US vehicle manufacturers(since 1996) and most others in the world(at least 2001).
Seeing as OBD-II is both a SAE(The Society of Automotive Engineers) and a ISO standard, I'm going to make the assumption that someone between the two knew how to program and was alright with the usage.
As an aside, any time your outside area of expertise, you may not want to jump someone for what may be common usage in another area.  It's obvious (as you did not understand the OP's usage of PID) that you have not spent any time in automotive diagnostics or you would have known what a PID was in the context of the OBD-II, which the OP made quite clear.  Plus this is the Electrical Engineering SE not a programming one, why make the assumption? 

EDIT:  @Lundin It looks like you do know what OBD-II is(or at least the canbus), so why the comment about the usage of PID??