This will plug into the red connector in the tail section and allow you to read codes, as well as clear them. I have been unsuccessful in clearing codes even after pulling the battery cable, and this will get rid of them immediately, assuming the problem has been rectified. I also wire in a dealer mode switch as well so that you can reset your service interval using this tool.
This will read engine codes, does not read ABS fault codes. ABS fault codes do seem to go away right after fixing them (and can be viewed on the dash with the dealer switch turned on).