Automatic speed limiter

Automatic speed limiter

Updated 10/4/2021

Automatic speed limiter

The Automatic Speed Limiter (ASLAutomatic Speed Limiter) function helps the driver to adapt the car's maximum speed to the speed shown on the road signs.

Symbol for automatic speed limiter

P5-1507-Automatic Speed Limiter symbol 10x10

The sign symbol (displayed alongside the stored speed, "70", in the centre of the speedometer) can be shown in three colours with the following meanings:

Colour of sign symbol


Greenish yellow

The automatic speed limiter is active


The automatic speed limiter is set in standby mode


Automatic speed limiter is in temporary standby mode - e.g. due to a road sign not being read.

Speed information from road signs

The automatic speed limiter uses speed information from the Road Sign Information (RSIRoad Sign Information) function to automatically adapt the car's maximum speed.

Road sign information bases its information on the speed limit road signs that the car passes, plus map data. Physical signs passed have top priority, which may be necessary in the case of roadworks, for example.

If road sign information cannot interpret and provide speed information to the driver support systems, the automatic speed limiter is set to standby mode and changes to the normal speed limiter. In such cases the driver must intervene and brake to a suitable speed.

The automatic speed limiter will be reactivated when road sign information can once again interpret and provide speed information.


Even if the driver clearly sees the speed-related road sign, the speed information from the Road Sign Information* (RSI) function to ASL may be incorrect – in such cases the driver must intervene him/herself and accelerate or brake to a suitable speed.

Tolerance level for automatic speed limiter

The automatic speed limiter can be set to different tolerance levels. The tolerance is adjusted in the same way as the speed setting is in the speed limiter.

If, for example, the car follows a signed speed limit of 70km/h (43 mph) the driver can instead choose to allow the car to maintain 75 km/h (47 mph).

The tolerance is followed until a road sign with a lower or higher speed is passed - then the car follows the new signed speed limit instead and the tolerance is deleted from the memory.


The maximum selectable tolerance is +/- 10 km/h (5 mph).


  • The function is supplementary driver support intended to facilitate driving and make it safer – it cannot handle all situations in all traffic, weather and road conditions.
  • The driver is advised to read all sections in the Owner's Manual that relate to this function to learn about factors such as its limitations and what the driver should be aware of before using the system.
  • Driver support functions are not a substitute for the driver's attention and judgement. The driver is always responsible for ensuring the car is driven in a safe manner, at the appropriate speed, with an appropriate distance to other vehicles, and in accordance with current traffic rules and regulations.

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