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Warning and auto-braking while backing up*

There are systems in the vehicle that can help the driver detect obstacles when backing up and even automatically brake the vehicle if the driver does not react in time.

The functions Rear Auto Brake (RAB)* and Cross Traffic Alert (CTA) are only active when the vehicle is moving backward or if reverse gear is engaged.

If an obstacle is detected:
  1. A warning signal and the Park Assist graphic illuminate to indicate the location of the obstacle.
  2. If the driver does not react to the warning and a collision is unavoidable, the vehicle may automatically brake, and a message will appear explaining why the brakes were applied.

If the accelerator pedal is depressed forcibly, the vehicle will back up even after auto-braking.

 Warning

  • The functions are supplementary driver support intended to facilitate driving and help make it safer – they cannot handle all situations in all traffic, weather and road conditions.
  • The driver is advised to read all sections in the Manual about these functions to learn of limitations, which the driver must be aware of before using the functions.
  • Driver support functions are not a substitute for the driver's attention and judgment. The driver is always responsible for ensuring the vehicle 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.

 Note

The functions use the vehicle's sensors and radar units, which have certain general limitations.

Obstacles directly behind the vehicle

Rear Auto Brake is designed to help the driver detect stationary obstacles directly behind the vehicle when backing up.

This function is primarily designed to detect stationary objects that are taller than the rear bumper and not, for example, moving vehicles.

Auto-braking with Rear Auto Brake is active at speeds under 10 km/h (6 mph).

The auto brake needs to be deactivated before entering automatic car washes and may also need to be deactivated to avoid undesirable interventions, e.g. when backing up in tall grass.

Obstacles from the side

Cross Traffic Alert is intended to help the driver detect vehicles crossing behind the vehicle while backing up.

This function is primarily designed to detect larger moving vehicles, but in certain cases can also detect pedestrians or smaller objects such as bicycles.

Auto-braking with Cross Traffic Alert is active at speeds under 15 km/h (9 mph).

The auto brake needs to be deactivated before entering automatic car washes and may also need to be deactivated to avoid undesirable interventions, e.g. when backing up in tall grass.

Examples of detection and limitations

PS2-2007-Cross Traffic Alert detection of crossing traffic
Examples of areas in which the function can help the driver detect obstacles while backing up.

The function's sensors cannot detect movements in traffic through other parked vehicles or objects blocking the vehicle. Here are some examples of when approaching vehicles can therefore not be detected until they are very close.

PS2-2007-Cross Traffic Alert limitations of detecting crossing traffic
The vehicle is parked very far into a parking space.
PS2-2007-Cross Traffic Alert limitations in angled parking
In a diagonal parking space, the sensors may be completely blocked on one side of your vehicle.
  1. PS-Icon circle 1Blind zone
  2. PS-Icon circle 2The function's field of vision

However, as you back your vehicle slowly out of a parking space, CTA's field of vision changes in relation to the obstructing vehicle/object and its blind zone is reduced.

Backing up with equipment connected to the towbar

RAB and CTA are automatically deactivated when a trailer, bicycle holder or similar is connected to the trailer contact. If the connected equipment does not have an electrical connection, RAB and CTA must be deactivated manually via the button in the center display.

  1. * Option/accessory.

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