I have not messed with the PCM/TCM off of my 2009 CC Silvy and dont want to. So i bought a used set.
I read the tune on the original set and then flashed the spare set but the VIN did not change and when I try to start the truck Nothing. I put my original set back in and everything back to normal.

Spare set comes from a 2007 silvy and mine is a 2009.

Im using HP Tuners