Here's the Volvo spin on OBD II. Volvo had code reporting before OBD II became universal. They had much more info available than required by OBD II. Vadis, currently, and earlier Volvo scan tools, read all this information. For example, climate control, and power seat info. When OBD II came around, Volvo converted only the codes for the OBD II subset and ported them to the OBD socket. That's why generic scan tools can't read all available Volvo codes. WWW.OBD-2.com has made an attempt to read other codes thru the OBD II socket, but it is not fully functional at this point. This tool will reset some Service Reminder Lights (see website for info) and all Check Engine Lights. Newer models allow Service Reminder Lights to be reset without tools using often published procedure.