I have an 02 Sierra with turbo LM7.
I lost my MPVI2, so purchased a new MPVI3. My software recognizes it until it is plugged into OBDII port. Port is 100% functional, tested with voltmeter, scanner, and my friends MPVI2. We tried everything, swapping cables, 3 laptops etc. We actually pulled the tune with my friends MPVI2.
Anyone have anything similar happening, and if so what was the issue?
I have reinstalled software over 10x. Have resynched even more.