i wanted to know for a 2000 CLK 430 two door, when you turn the car off, do you have to turn the radio off or when you take the key out of the ignition does that automatically turn the radio off? Do you have to physically turn the radio off. It's a bet, I say when you leave the radio on and just take the key out, it can drain your battery. He says that when you take key out the ignition, it automatiocally shuts the radio off, even thou when you put the key back in the ignition, the radio automatically comes on. I know its stupid , but i need to know so i can brag if i am right