I have a SnapOn Euro Checker Scan Tool. I bought it new for $600. It includes all cables and software needed to do readings and resets on Audi, VW, BMW, Volvo, MB, etc.

For your 97, this will do service lights, HVAC codes, and others. (For my 92, it doesn't do much of anything...)

Due to it's incompatibity with the pre-CE cars, I am selling the unit. $400 obo.

-David