Collision warning system* - operation

"Collision Warning with Auto Brake and Cyclist and Pedestrian Detection" is an aid to assist the driver when there is a risk of colliding with a pedestrian, bicycle or vehicle in front that are stationary or moving in the same direction.

Warning signals On and Off

P4-1220-Collision Warning - Komponentplacering Sedan
1. Acoustic and visual warning signal in the event of a collision risk1.

You can select whether the collision warning system's acoustic and visual warning signals should be switched on or off.

When starting the engine, the setting that was selected when the engine was switched off is obtained automatically.


The Brake Support and Auto Brake functions are always enabled - they cannot be deactivated.

Settings for the collision warning system are made via the centre console's screen and the menu system MY CAR, see MY CAR.

Light and acoustic signals

When the collision warning system's light and acoustic warnings are activated, the warning lamp (no. [1] in previous illustration) is tested each time the engine is started by briefly illuminating the warning lamp's separate points of light.

After starting the engine, both the light and acoustic signals can be switched off:

  • Search for Collision warning in Driver support system in the menu system MY CAR MY CAR - and there select to uncheck the function.

Acoustic signal

After starting the engine the warning sound can be activated/deactivated separately:

  • Search for Warning sound in Collision warning in the menu system MY CAR MY CAR - and there select On or Off.

Following which, the collision warning system is only indicated with a light signal.

Set warning distance

The warning distance regulates the distance at which the visual and acoustic warnings are deployed.

  • Search for Warning distance in Collision warning in the menu system MY CAR MY CAR - and there select Long, Normal or Short.

The warning distance determines the system's sensitivity. Warning distance Long provides an earlier warning. First test with Long and if this setting produces too many warnings, which could be perceived as irritating in certain situations, then change to warning distance Normal.

Only use warning distance Short in exceptional cases, e.g. for dynamic driving.


When the adaptive cruise control is in use the warning lamp and warning sound will be used by the cruise control even if the collision warning system is switched off.

The collision warning system warns the driver in the event of a risk of a collision, but the function cannot shorten driver reaction time.

In order for the collision warning system to be effective - always drive with Distance Warning set at time interval 4–5.


Even if the warning distance has been set to Long warnings could be perceived as being late in certain situations, e.g. when there are large differences in speed or if vehicles in front brake heavily.


No automatic system can guarantee 100 % correct function in all situations. Therefore, never test Collision Warning with Auto Brake by driving at people or vehicles - this may cause severe damage and injury and risk lives.

Checking settings

The current settings can be controlled via the centre console's screen and the menu system MY CAR.


P3-1220-Collision Warning - Komponent-Tvätt
Camera and radar sensor2.

For the sensors to work correctly, they must be kept clear of dirt, ice and snow, and be cleaned regularly with water and car shampoo.


Dirt, ice and snow covering the sensors will reduce their function and may prevent measurement.
  1. * Option/accessory.
  2. 1 The illustration is schematic - car model and details may differ.
  3. 2 NOTE: The illustration is schematic - details may vary depending on car model.

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