Damned. It wasn't the ECU either. I'm running out ideas.
I've googled some other Cat models too and seems M1000 have had same issues. Bad thing is there's no solution found on those topics as sleds has been parted out or totalled some other way :/
hi, I am French, I have exactly the same problem and I did exactly the same test as you!
have you found the problem because I have been blocking for 4 months?