If you have a newer Mercedes Benz model, you were probably given a fob-like key to start your car with a push-to-start button. If you don't want to use that button and would rather put your key into the ignition, here's what you can do. First, take off the push-to-start button by pulling it out. Once the button is out, put the key in the ignition and turn. A commenter also noted that this hack works for Chrysler Minivans.