System Outline

* In the pre-collision system (PCS), the seat belt is retracted by a motor upon receiving signals from the pre-collision sensor (Millimeter wave radar sensor + distance control ECU) and skid control ECU, in order to optimize the restraint performance.

* The skid control ECU sends trigger signals to the seat belt control ECU through CAN communication when it detects certain vehicle conditions such as a spin, under-steer or sudden braking. The seat belt control ECU activates the PCS upon receiving the signals

* The pre-collision sensor detects on-coming vehicles or objects on the road ahead using a millimeter wave radar, and determines in advance whether a collision is unavoidable by using information from the distance control ECU such as the position, speed and on-coming route of the object. The distance control ECU then sends signals to the seat belt control ECU through CAN communication to activate the PCS motor to retract the seat belt before a crash. This function will activate even if the vehicle speed is 0 km/h if the conditions are right.

* If the pre-collision system experiences a failure, 'CHECK PCS SYSTEM' will appear on the multi-information display in the meter. The PCS warning lamp will be lit up as well. If the system is not available due to dirt on the radar, 'PCS NOT AVAILABLE NOW' will appear and the warning lamp will blink.