Identifying Cal Files for Organizing
So with the OBDI cals it took a few years to get things worked out, but today we can identify calibrations by Mask ID, then by BCC. We tend to use the latest cals available for a particular mask and vehicle combination and we know enough to have worked out that some masks can be used in non-native ecm's. But in the world of OBDII we're still copying cals from every vehicle we can get our hands on. Which leads to questions such as "How many cals are redundant except for VIN?" and "How many cals are 'superceded' and shouldn't be used?" "How many cals are 'special cases' such as the ones intended to be used only when a customer complains of cell phone interference?" And finally, is it possible to "break apart" a .cal file, group together a combination of the best cals, and reassemble it into a working file? Should this even be done?
Seems like there really should be a way to:
1) Identify cal by major features
------ Operating System number
------ Engine Cal number
------ Fuel System Cal number
------ System Cal number
------ Transmission Cal number
------ Other cal numbers?
2) Determine which if any of the numbers above are the latest
3) Sort cals based on numbers above
And ultimately, 4) assemble complete calibrations from individual component cals possibly based on cal number above.
The OS number appears to be roughly equivalent to the Mask ID. The same OS may be used across different years just like the same mask can be used across different years. It may also be used in different PCM's or VCM's. The cal variables are grouped together in tables such as the Engine Calibration, Fuel Calibration, and others as listed above. Any changes to the variables will result in a different calibration number. So, it follows that updates and reflashes would create calibrations with different numbers under the OS, but the OS isn't likely to change. This also provides a very nice way to organize calibrations, just like MaskID.
As far as update history, currently I'm looking at a handful of files in hex editor which have a VIN stored at location 0. That information can be used to identify the history through an online resource. It's a cumbersome process but it will work. It's going to take a long time to develop a master list of calibrations this way but it is possible. The rest, well, who knows if it will ever happen...
