I use BR-3 interface for my 1995 C220.
The Windows version software does not work but the DOS version works.

I can get some basic data from OBDII such as rpm, AMM, coolant temperature, calculated load...etc. Should be able to pull DTC. Since my car is free from trouble now, I got "0" in response.

It's only $88 for the interface. Software is free download from website.

check this
http://www.obddiagnostics.com/