I have an 03 Z06. I was at track last night and went to upload tune and ran into this problem. This is the error I am getting. I have done all things that I have found. The display on my dash says service Traction control guages not working, no fuel pump also says deduce engine power. I have checked all fuses including the ones in passenger floor board. Found none blown. Thanks for all your help. I have unhooked battery and tried again same issue. Only thing I can think of left is fried pcm or software issue. I have done a search and come up with a quote from Bill@HPtuners below.
If you receive an Unable to locate VCM error
The most common cause for this is that either your cable is not connected to the obd2 port or your key is not in the Run(On) position OR you could have a blown fuse in your fuse panel.
Commonly the obd2 port fuse is also the cigarette lighter fuse so thats the first to check, but this can vary from vehicle to vehicle as corvettes use a different REAR FOG/ALDL/TOP SW fuse located under the passenger floor.
Its rare that these issues are caused by our software & are usually a simple electrical or connection issue, however If you've checked all of your fuses & connections please contact support at hptuners.com with a vcm suite infolog while connected to the vehicle along with the year/make/model of the vehicle in question so that we can try to troubleshoot further.