Collision Warning System with Braking Function

The Collision Warning System with Braking Function is an advanced safety feature designed to prevent or mitigate rear-end collisions. It provides both visual and auditory alert notifications to the driver and, if necessary, applies automatic braking to reduce the risk of an accident.

Depending on the country, model, and equipment configuration, the system may also include a brief brake intervention to warn the driver even before they step on the brake pedal.

How the System Works

When a potential collision is detected, the system first issues a visual pre-warning, followed by an audible emergency warning. Before the driver applies the brakes, the system pre-fills the braking circuit and lowers the activation threshold of the brake assist system. This process shortens braking distance once the pedal is pressed.

If the driver’s deceleration is insufficient, the system provides additional braking automatically. When the driver fails to react, the system initiates emergency braking, potentially applying full braking power depending on the situation. The braking intervention can be overridden by pressing the accelerator pedal or steering actively.

Technical Configurations

There are three main technical specifications for collision warning systems with braking functions, depending on the sensors used:

1. Camera-Based Collision Warning

This version relies solely on the KAFAS camera to detect traffic ahead.

Speed range: 5 km/h – 250 km/h (function temporarily deactivates above 250 km/h)
Braking range: 5 km/h – 85 km/h
Maximum deceleration: approx. 50 km/h

2. Data Fusion: KAFAS Camera + Front Radar Sensor

Combines camera and car radar data for better object detection.

Speed range: 5 km/h – 250 km/h
Braking range: 5 km/h – 210 km/h
Maximum deceleration: approx. 60 km/h

3. Data Fusion: KAFAS Camera + Front Long-Range Radar Sensor

Offers the best detection range and reliability using long-range radar.

Speed range: 5 km/h – 250 km/h
Braking range: 5 km/h – 210 km/h
Maximum deceleration: approx. 80 km/h

If the driver is distracted, the Driver Camera System (DCS) detects inattention and adjusts the warning timing to alert the driver earlier.

Required Vehicle Equipment

Depending on configuration, the system requires specific equipment packages such as:

Camera-Based: SA5AV (Active Guard), SA5AO (Active Protection Plus), or SA5AS (Driving Assistant)
Radar Fusion: SA5AQ (Active Protection Plus for specific models) or SA5DF (Active Cruise Control with Stop & Go)
Long-Range Radar Fusion: SA5AU (Driving Assistant Professional) or SA5DF

Operating the Function

The collision warning with braking function can be disabled by long-pressing the Intelligent Safety button, but it automatically reactivates after restarting the vehicle.

Warning timing can be adjusted in the car’s menu:

CAR → Settings → Driver Assistance → Safety & Warnings → Front Collision Warning System
Choose the desired warning timing (Early, Medium, Late). Selecting “Late” disables pre-warning and only triggers emergency warnings.

Participating Control Units

The system integrates multiple vehicle control modules, including:

KAFAS Camera, Front Radar Sensor (FRS), Long-Range Radar (FRSF), Dynamic Stability Control (DSC), Body Domain Controller (BDC), Driver Camera System (DCS), Airbag Control Module (ACSM), Head Unit (HU), and Instrument Cluster (KOMBI).

Functional Prerequisites

Operating range: 5 km/h – 250 km/h
Between 210 km/h and 250 km/h, only short brake interventions occur without automatic deceleration.
Above 250 km/h, the system is temporarily deactivated.

Limitations

The performance of the car collision warning system may be affected under the following conditions:

Heavy rain, fog, or snow
Low visibility or strong backlighting
Disabled or limited DSC
Dirty sensors or camera lens
Sharp curves or narrow lanes
Extreme speed differences between vehicles
Sudden entry or braking of the vehicle ahead
Poor lighting at night
During camera calibration
For models equipped with radar sensors, braking intervention is only available in approved regions. The exact braking behavior depends heavily on driving conditions.

Conclusion

The Collision Warning System with Braking Function represents a crucial advancement in automotive safety, helping prevent accidents before they occur. Through the combination of camera and radar data, intelligent alert notifications, and automatic braking functions, this system greatly enhances driver awareness and vehicle response in critical moments.