[emiliof56]

Hello guys

 
I would like to understand what is the logic behind VAG group software updates.
I know sometimes for a given part number, when updating the software, the last letter may change, but other times just the revision changes from 0001 to 0002 or so.
What is the correct way to identify what ecu can be update to what softwares, and what software versions can be crossflashed on a given part number?

Thank you

[pupu144]

Read related TPIs.

There is very little logic.
However, usually you can safely flash ECU to the latest available software version.
Meaning, 123 456 789 AB v0001 to 123 456 789 AB v9000, for example. As it mostly is just bugfixes or optimizations.

When the letters change, that when you need to be extra careful! Some modules can be updated to a certain SW version only (not the latest), sometimes it is dependent on the car model where it is installed, sometimes it depends on model year, etc.

That is why with VAG cars you ALWAYS MUST read TPI related to every software update.

[vojta610]

Hi, where can I find that it is possible to flash my ECU?

[pupu144]

You can use this website - https://vag-flashinfo.de/


They also have some great info disclaimer apparently, on this very topic:

A simple increase of the version number (like 9970->9979) is surely a compatible update.

Things like 0100 -> 0600 would rather be incompatible because of the huge jump. Often, VW use this for newer hardware revisions.
A big different in filesize is also an indicator that an update might be incompatible.

And then there are index changes. There is also no general logic to apply (imho).

Because of all that (and sometimes there are post-update-steps described in TPI): always search an applicable TPI with a flash info table.