anyone got this problem before?
I have tried to change the vin. it says na00000000000000 in the vin in efilive and techII
I even tried to upload a new file from gm, with new vin in techII. Still return vin na00000000000000 after full flash.

yes of course I have tried to change it with the scan tool, and in the pcm tool in tune.

Ecm takes the tune file fine, but not the vin. M I missing something here?

The ecm had a valid vin before, and I have the original os for it. But when I full flash it back it takes the tune, but not the vin..
The ecm has newer been modified in the chip. What I did was to upload a custom os for it, and then flash it with a correct parameters tune.
After that, no more vin for me