I bought the tool to see why my light came on and to reset it to get an inspection sticker. I looked up on several web sites to see what tool was recommended. This one was noted in consumer reports as a best buy at double the price! It by no means has all the bells and whistles and there are models with many more readouts however this one can give you the code number then explains it in english right down to what cyl. might be missfiring or where an injector my be messed up. It then can reset the codes with one push of the reset button.