The only cheap scanner I know that does most of the stuff is the foxwell 510. I have one of those and have cleared codes on r170's before but I dont remember the year now. The nice part about the foxwell is you can take it with you unlike the laptop setup ones. Its slow but it works. There is an addon for it that hooks to the underhood plug on the older cars too if needed. Also you can buy software from them for other brands of cars later if need be. I have bmw, chrysler and mercedes in mine.

If its just the code being in there from previous problems you have fixed then going to a local garage and asking them to clear the codes and seeing if they come back is an option. Personally I like having a way to clear them myself so the foxwell might be something to consider. Make sure its the 510. Mines a 510 elite.

Its $189 on amazon.