Does it have a "Towing" switch? On mine it has a picture of the back end of a tow truck with a little crane on it. That turns off the 'exterior' motion sensor.
Fine, but not too far away, it might start affecting my sleep.
Does a 2003 R230 have a normal key looking Keyless Go key? Has the metal blade been taken out from the key, sounds odd. I understand if it had the older credit card like KG key, then the metal blade would need to be somewhere (likely lost )