Unidentified Beeper Button -- Mercedes C320cdi 2006

We recently purchased a Mercedes C320cdi 2006. There is an on/off switch on the center console. The button makes a beep… beep… beep noise, but otherwise has no impact on the performance or environment of the car. The manual is silent on the question of the button. Does anyone have thoughts about what it might be for?? Thoughts and ideas would be greatly appreciated. Thank you!

Rear parking sensor buttom maybe?

Thanks for your thoughts. That was our thought (initally), but the button beeps no matter what (with the car in park, neutral, drive, going backwards, and etc). Plus, the rear parking sensor goes off whilst the ‘beeper button’ is beeping. We are stumped!

Do you have the right manual for your car? I can’t imagine a button that wouldn’t be covered by the manual.

Regardless, wouldn’t a call to a Mercedes dealer resolve this in about two minutes?