I have a 2000 CLK 430. How can I turn off that sound when I start up the car and sometimes it makes the same sound when I shut the car off. I think it is the cell phone chime; it lasts for about 2 seconds of so,(I don't know what else to call it). I don't have an in car phone but I think that's it. any ideas?

I have an '01 and mine does it too, I also think it does it at other times. I though it was like an error warning thing telling me something was wrong, I just got the car and the previous owner took the fog lights out of the rear bc he didn't like the look of them so, it shows an error code.