Thanks!
Well, I called the MB dealership that sold me the car, and the shop tech said the code I have is correct. But when I explained the C--ERR situation, he said, "Oops, no, something's not right. Come in, and we'll take a look at it for you. If you go to your local dealership [Brooklyn], they might charge you, so come to us [Nanuet]." I was told it could be as simple as unplugging the radio and plugging it in again.
So Saturday I head up there. I'll let you know what happens!!
