Some of the specific engineering details of the OIS link may be kept under wraps (to discourage attempts to maliciously influence the test) but the fact remains that there are a significant of vehicles out there with mismatched VINs, as a result of salvage repairs, owner modifications, and such.

Some of the vehicle owners may not even be aware of this, and we (as repair technicians) should be given sufficient information on a failing VIR to proceed with an appropriate repair, and not just be red-flagged automatically (and perhaps surreptitiously) as a cheater.

Michael Barry
Technician
Quick Stop Smog & More
Sacramento, California, USA