Quote Originally Posted by Blacky View Post
The 2022 ECMs have an updated boot block that enforces a digital signature check that cannot be bypassed.
The 2021 ECMs have a boot block that contained a "bug" that could be exploited to bypass the digital signature - Cummins fixed that bug in the 2022 boot block update.
So no, you can't use 2021 ECM to gain access to a 2022 ECM, the only way would be to change the boot block in the 2022 back to the 2021 boot block, but you can't do that until/unless you supply the correct digital signature (or bypass it, which cannot be done).

Warning: Getting your 2021 ECM flashed at a dealer can update the boot block to the 2022 boot block thus rendering the ECM no longer tunable.

Regards
Paul
So basically if dealer flashes the 2021 ECM you WILL be locked out or will possibly be locked out?