Adaptive Cruise Control – function

Updated 2023-06-08

ACC is an optional system designed to assist the driver by maintaining a set speed or a set time interval to the vehicle ahead. It is primarily intended for use on long straight roads in steady traffic, such as on highways and other main roads.

Function

Adaptive Cruise Control consists of:

A cruise control system to maintain a set speed
A system to maintain a set distance to the vehicle ahead, which is expressed as a time interval. For example, you can choose to remain approximately 2 seconds behind the vehicle ahead. The actual distance required to maintain a 2-second interval will vary according the speed of the vehicles.

Warning

Adaptive Cruise Control is not a collision avoidance system. The driver is always responsible for applying the brakes if the system does not detect another vehicle.
Adaptive Cruise Control does not react to people or animals, or small vehicles such as bicycles and motorcycles. It also does not react to slow moving, parked or approaching vehicles, or stationary objects.
Do not use Adaptive Cruise Control in demanding driving conditions such as city driving or other heavy traffic situations, in slippery conditions, when there is a great deal of water or slush on the road, during heavy rain or snow, in poor visibility, on winding roads or on highway on- or off-ramps.

The distance to the vehicle ahead (in the same lane) is monitored by a radar sensor. Your vehicle's speed is regulated by accelerating and braking. The brakes may emit a sound when they are being modulated by the adaptive cruise control system. This is normal.

Warning

The brake pedal moves when the adaptive cruise control system modulates the brakes. Do not rest your foot under the brake pedal.

The ACC system is designed to smoothly regulate speed. However, the driver must apply the brakes in situations that require immediate braking. This applies when there are great differences in speed between vehicles, or if the vehicle ahead brakes suddenly.

Warning

Due to limitations in the radar sensor, braking may occur unexpectedly or not at all, see Adaptive Cruise Control – limitations.

Adaptive Cruise Control can be put in active mode at any permitted speed. However, if the vehicle's speed falls below 18 mph (30 km/h) or if engine speed (rpm) becomes too low, ACC disengages (goes into standby mode) and will no longer modulate the brakes. The driver will then have to maintain a safe distance to the vehicle ahead.

Warning

When Adaptive Cruise Control is in standby mode or is switched off completely, the brakes will not be modulated automatically. The driver must assume full control over the vehicle.

Warning light—driver braking required

Adaptive Cruise Control can exert brake force that is equivalent to approximately 40% of the vehicle's total braking capacity. In situations requiring more brake force than ACC can provide and if the driver does not apply the brakes, an audible signal from the Collision Warning system will sound and warning light will illuminate (see Collision warning * – function) in the windshield to alert the driver to react.

Note

Strong sunlight, reflections, extreme light contrasts, the use of sunglasses, or if the driver is not looking straight ahead may make the warning symbol in the windshield difficult to see.

Warning

Adaptive Cruise Control only warns of vehicles detected by the radar sensor, see Adaptive Cruise Control – limitations. In some cases there may be no warning or the warning may be delayed. The driver should always apply the brakes when necessary.

Steep inclines and/or heavy loads

ACC is primarily intended for use on fairly level roads. The system may have difficulty maintaining the correct distance to a vehicle ahead on steep inclines, if the vehicle is carrying a heavy load or is towing a trailer. In these situations, the driver should always be prepared to apply the brakes if necessary.