Mercedes-Benz C-Class (W205) 2015 - 2021 Owners Manual: Function of Active Speed Limit Assist

If a change in the speed limit is detected and Active Distance Assist DISTRONIC is activated, Active Distance Assist DISTRONIC adapts this new speed as the stored speed.

The driven speed is adjusted when the vehicle is level with the traffic sign at the latest. In the case of signs indicating entry into an urban area, the speed is adapted according to the speed permitted within the urban area. The speed limit display in the instrument display is always updated when the vehicle is level with the traffic sign.

If there is no speed restriction on an unlimited stretch of road (e.g. on a freeway), the recommended speed is adopted as the stored speed.

The system uses the speed stored on an unlimited stretch of road as the recommended speed.

If you do not alter the stored speed on an unlimited stretch of road, the recommended speed is 80 mph (130 km/h).

If Active Distance Assist DISTRONIC has been put into passive mode by pressing the accelerator pedal, only speed limits which are higher than the set speed are adopted.

Active Speed Limit Assist is only an aid. The driver is responsible for keeping a safe distance to the vehicle in front, for vehicle speed and for braking in good time. The maximum permissible speed also depends on factors such as the road surface and traffic conditions.

System limitations

Temporary speed restrictions (e.g. for a certain time or due to weather conditions) cannot be properly detected by the system. The maximum permissible speed applying for a vehicle with a trailer is not detected by the system. In these situations you must adjust your speed yourself.