System Description

PRE-COLLISION: PRE-COLLISION SYSTEM (w/o Driver Monitor Camera): SYSTEM DESCRIPTION

1. PRE-COLLISION SYSTEM DESCRIPTION

(a) The pre-collision system detects vehicles and obstacles in front of the vehicle and performs the following: 1) optimally uses system controls to avoid collisions, and 2) uses system controls to reduce impact during a collision.

2. PRE-COLLISION DETECTION OUTLINE

(a) Front collision detection

(1) The driving support ECU receives information about vehicles and obstacles in front of the vehicle from the front millimeter wave radar sensor. Then, based on vehicle speed, the driving support ECU determines, in advance, the risk of a collision and if a collision is unavoidable.

(b) Sudden braking detection

(1) The skid control ECU activates the pre-collision seat belts when it detects sudden braking. Sudden braking is determined based on brake oil pressure and other information from the master cylinder pressure sensor.

(c) Vehicle control impossible judgment

(1) The pre-collision seat belts are activated when it is determined that there is a high probability that the vehicle cannot be controlled. The judgment is based on vehicle stability information from the yaw rate sensor and steering angle sensor.

(d) Component





3. PRE-CRASH SAFETY SYSTEM CONTROL DESCRIPTION





4. PRE-COLLISION SEAT BELT CONTROL

(a) When the system determines that a collision with an obstacle is unavoidable, that sudden braking has occurred, or that vehicle control is impossible, the system performs seat belt control. During seat belt control, slack in the seat belts is reduced to increase occupant restraint and aid the pretensioner.

5. PRE-COLLISION BRAKE ASSIST CONTROL

(a) When the system determines that there is a risk of colliding with an obstacle in front of the vehicle, break assist is set to standby mode. Then, when the driver depresses the brake pedal, the hydraulic brake pressure is increased to improve braking effectiveness.

6. AIR SUSPENSION CONTROL

(a) When it is determined that there is a risk of colliding with an obstacle in front of the vehicle, the air suspension is operated to control the damping force, suppress nose diving and rolling, and support collision avoidance through steering.

7. PRE-COLLISION SYSTEM (PCS) OPERATING CONDITION





HINT
* o: Operation
* X: Not operation
* *1: Inoperative parts are different depending on malfunction areas
* *2: Only operates when seat belt is fastened
* *3: Pre-collision seat belts may operate when brakes are suddenly applied

8. PRECAUTION FOR FRONT MILLIMETER WAVE RADAR SENSOR

(a) When the front millimeter wave radar sensor detects an object in front of the vehicle under the conditions described below, the driving support ECU may determine that a collision is unavoidable, and activate the pre-collision system. However, this is not abnormal.





HINT
* The pre-collision system will not activate when the pre-collision sensor detects safety cones and other plastic objects.
* The pre-collision system may or may not activate when the pre-collision sensor detects the following objects: people, bicycles, motorcycles, trees, animals and snow fences.