See also:

Making adjustments in 1 mph (Canada: 1 km/h) increments
Briefly press the cruise control lever to the pressure point, up 1 for a higher speed or down 2 for a lower speed. The last speed stored is increased or reduced. ...

Releasing the parking lock manually
In the event of an electrical malfunction, it is possible to release the selector lever lock manually to move it out of position P, e.g. if you wish to tow the vehicle away. Do not use any s ...

Problems with your vehicle
If you should experience a problem with your vehicle, particularly one that you believe may affect its safe operation, we urge you to contact an authorized Mercedes-Benz Center immediately to h ...