i have a 05 w211 e55 amg SBC was damaged due to accident, just replaced it with another used one. while trying to bleed the brakes with DAS i get an Note " Voltage at control unit SBC:0.2V" . what does that mean ? im i connecting the battery charger at the wrong place ? i connected the charger in the trunk, positive on the battery and negative to the body of the car.