There are a couple of threads on people developing software to read the canbus and manipulate the data. I'm using an arduino with canbus shield to interface with the can us in my Touareg. The arduino + canbus is not a buy and implement item. There's programing involved to make it do what you want. I remember running across a post that listed a USB canbus device that worked out of the box more or less. I'll see if I can find that post.