Going through the same thing with my car. First go to wal-mart and buy a code reader like the Innova 3100. My battery was disconnected. I have since put on 400 miles and the 2A EV E codes which are all emmissions related are still off line. I was told by a very reliable source that it can take up to 700 miles of driving to reset the factory system. You can also try and find a Dealer with Star diagnostic tools for Mercedes and they can hard program the sensors. I don't know what that costs. If you want pm me your phone number I can get you around the front plate issue and if you are close you can use the code reader I have to see what is going on. Dave