See also:

Warranty
The Service and Warranty Information booklet contains detailed information about the warranties covering your vehicle. Your authorized Mercedes-Benz Center will exchange or repair any defective ...

Checking tire pressure electronically
  Make sure that the SmartKey is in position 2 in the ignition lock.   Press the or button on the steering wheel to select the Service menu.   Press the or button to sel ...

Locking the vehicle (mechanical key)
If the vehicle can no longer be locked with the SmartKey, use the mechanical key. Open the driver's door. Close the front-passenger door, the rear doors and the trunk lid. Press the locking ...