4 year old bump LOL, I'm fighting a 2001 the guy has a CTS that he assure's is just a display I tried the 441 and 6006 OS ect. Trying the vin for a 02 tonight in the 441 OS I already tried the 02 vin on the 6006 OS with no luck. Won't the oil life be screwed going back to the 01 OS after flashing the 02 ones? I might have to try a few more vin#'s since the on I have is for the 6006 OS. Also the vin is not carrying over from the tune file so I've been changing it in the scan tool, any other suggestions to get a CTS to work it's getting the "Not supported PID message" and shutting off?