My 1999 V70 is my first Volvo lemon with numerous electrical problems culminating in the failure of the ABS computor ($800 part ) and the main computor ($1200), that little metal box with the yellow sticker under the motor shroud on the front of the engine. It throws error codes from time to time and the check engine light comes on. The only service here in this part of Florida is the dealership who charges $145 to see what the car is complaining about and deploys draconian billing schemes like charging three tenths of an hour labor if the mechanic lifts the hood. I miss the old 740 and the times we had like driving through Greenwich Village in New York surrounded by dozens of roaring motorcycles of a female gang, and limping across the Mojave Desert with a broken fuel pump. The new Volvos are over-engineered puzzles that Volvo "technicians" scratch their heads over. I digress. Is there a way I can read error codes myself? Is there something that plugs into that socket between the front seats labeled as "OBD II" ? The last code demanded a new air mass sensor and then shut off after I paid the $145. Any tool for reading these at home? Thanks for your time and consideration.