2xLS1

iTrader: (25)

I need a detailed explanation of the ID #s that are displayed when you open .bin file. I have a spare PCM that I had dealer flashed with my VIN and when I compare the ID #s of the original PCM in my 99 and the spare PCM, the ID #s are different on the following:
Operating System
Engine Cal
Engine Diag
Fuel System
System
The ID #s are the same on the following:
TransCal
Trans Diag
Speedometer

Also what is the BCC:

I see these are the same #s that are displayed for segment 1-8 on LS1edit, but I never understood those either.

2xLS1

iTrader: (25)

Here are mine.

horist

From my understanding BCC is Broadcast Control Code ... not sure what it does
the various IDs are the Dealer versions of various softwarez... Like Windows 98 and windows 2000

These values change as GM makes changes to the source code

The CSums are Checksusm... they're values calculated to ensure the base code is correct ...


Above are based on observations and reading... not 100% if I'm write

2xLS1

iTrader: (25)

So then if you were to have a dealer reflash both PCMs at the same time all the ID #s on both PCMs would match?

horist

yes I believe so... I don't think these #s are hardware driven , I believe they're software driven...

gameover

the most important number is the Operating System ID. This is in effect the "version" of the operating system you have on your PCM, this is the code that controls everything.

The other numbers are calibration ID's. This is how GM keeps track of the particular versions of the calibration data that is stored in the PCM. Again it's another form of version control so a dealer can easily work out what's what. eg. Customer with 4L60E complains about sloppy shift, load trans calibration ID 1234567 that has firmer shift pressures etc.

Speedometer section contains the various calibrations for the speedo based on gear/tire combo's available for that model.