So you haven't taken it out of the box? Did you get a picture or part number when you bought it? You should at least compare part numbers to the one in your car. Rudy has been swaping TCU's with no problem and swears they are not VIN coded. I think you are making this harder on yourself than you need to. The seller may think you are a bad buyer. In the automotive world electronic parts are usually never refundable. this is very normal.