Questions about PID groups

[turbo_bu]

Looking at the PIDs listed under the 2001 OS (12212088) and noticed that there appears to be several different groups. I understand the SAE PIDS which are listed as 00xx (example 0011 is the TPS %). The next group has a prefix of 11 (example 1140 - which I have seen referenced as MAF signal). There are quite a few PIDs which start with 11xx, 12xx and 13xx. I found one reference from an earlier non LS OS (believe it might have been a vortec black box PCM) which listed some of these PIDs. It appears that some of the names match up, but some of them do not.


The next grouping has a 19xx prefix (and three 1Axx PIDs). Are these transmission PIDs? The one reference I found lists some 19xx PIDs and these have to do with the transmission variables.


The final group of PIDs has a FCxx prefix. For these I have not seen any mention of what they pertain too.


Is there a master list that can be referenced? I looked over the SAE documentation, but it obviously only covers the 00xx PIDs. And GM only threw in a few of those. The main section is the 11xx through the 19xx (and maybe the FCxx). I think that some / all of these are what are called "Enhanced PIDs". If so, then maybe the only documentation for them would have to come from GM.

[dzidaV8]

PIDs above 00FF are all manufacturer specific, and the information about them is proprietary and can change by model and year. I'm in a process of reverse engineering all the PIDs for LS1 PCM, but the work is very tedious and time expensive, so I'm not going to open source that information (at least not just yet).

I can tell you that the first two digits do not mean any PID group, PIDs have just some assigned numbers and that's it, e.g. There are misfire related PIDs with ID 11xx and 12xx.

Do you need any specific PID?

[turbo_bu]

I am currently working on a few different things trying to understand a 2001 OS that somebody did a disassembly on. I will go back and find the exact PIDs that I am working on to see if you had already figured them out or not. FWIW, here's the listing of PID's that I found which shows some of the higher numbers.

http://www.fastfieros.com/tech/vpw_communication_protocol.htm

[dzidaV8]

I know that document, very resourceful :)

I can help you with certain PIDs, sure.

[turbo_bu]

Are you using any kind of OBD II tool to help with the reverse engineering? I am looking at getting one to help understand what kind of string gets returned from a given request.

[dzidaV8]

I'm using AVT-842 cable, but just for seraching PIDs any ELM327 interface is enough.