I purchased a pre-owned 2000 E320 from the local MB dealer. I received 1 key, and the dealer ordered another key and a flat key (at no cost to me). The new key opened and locked the doors, but did not work in the ignition. A second key was ordered. This key worked. However, when I use this key I get a message in the LCD display which states "Brake Lining Wear" , and am advised to take it to the shop. The LCD also indicates "1 Malfunction". When I use the original key, I do not get this message, and the LCD indicates "No malfunctions". The vehicle has 14,500 miles, and when purchased had 13,500. I cannot imagine the brake pads needing replacement this soon. And why do I get the messge with the new key, but not the original one? Does the key have any memory chips or are these memory chips in the vehicle itself ? Any one else having problems with the electronic keys?