System Description [08/2014 - ]

WARNING: This page is about a different variant/trim than selected.

FUNCTION DESCRIPTION
1. Electronically Controlled Brake System
  1. Upon receiving signals from the skid control ECU, this system effects hydraulic pressure control at the four wheels.
2. Regenerative Brake Cooperative Control
  1. Controls hydraulic braking in order to recover electrical energy by utilizing the regenerative brake of the hybrid control system as much as possible.
3. Enhanced-VSC (Cooperative Control with EPS)
  1. Effects cooperative control with the power steering ECU in order to provide steering assist in accordance with the operating conditions of the vehicle.
4. Anti-lock Brake System (ABS)
  1. The ABS helps prevent the wheels from locking when the brakes are applied firmly or when braking on a slippery surface.
5. Electronic Brake force Distribution (EBD)
  1. The EBD control utilizes ABS, realizing proper brake force distribution between the front and rear wheels in accordance with the driving conditions. In addition, during braking while cornering, it also controls the brake forces of the right and left wheels, helping maintain vehicle behavior.
6. Brake Assist (BA)
  1. The primary purpose of brake assist is to provide an auxiliary brake force to assist a driver who cannot generate a large brake force during emergency braking, thus helping draw the vehicles braking performance.
7. Traction Control (TRAC)
  1. The TRAC helps restrain the slippage of the drive wheels if the driver depresses the accelerator pedal excessively when starting off or accelerating on a slippery surface.
8. Vehicle Stability Control (VSC)
  1. The VSC helps restrain sideways slippage of the vehicle during a strong front wheel skid or strong rear wheel skid, during cornering.
9. Hill-start Assist Control
  1. When the vehicle starts off on a steep or a slippery hill, Hill-start Assist Control performs 4-wheel hydraulic pressure control to prevent the vehicle from moving backward.

FUNCTION OF COMPONENTS

Component		Function
Brake Booster with Master Cylinder	Brake Actuator	Consists of four switching solenoid valves, two linear solenoid valves, eight control solenoid valves. Changes the brake fluid path based on the signals from the skid control ECU during the operations of the ABS with EBD, BA, TRAC, VSC, hill-start assist control, and Enhanced-VSC in order to control the fluid pressure that is applied to the wheel cylinders.
	Hydraulic Brake Booster	Generates hydraulic pressure in accordance with the amount of effort applied to the brake pedal by the driver. When a malfunction occurs in the brake system, the hydraulic brake booster supplies the fluid pressure (which is generated by the brake pedal effort) directly to the wheel cylinders.
	Stroke Simulator	Generates a pedal stroke during braking in accordance with the drivers pedal effort.
Brake Actuator	Skid Control ECU	Monitors the driving conditions of the vehicle in accordance with the signals received from the sensors and through cooperative control with the power management control ECU and power steering ECU calculates the required amount of braking force, and controls the brake actuator. Judges the vehicle driving condition based on signals from each sensor, and controls ABS with EBD, BA, TRAC, Enhanced-VSC and hill-start assist control. Operates the brake booster pump to control accumulator pressure based on accumulator pressure sensor signal.
Skid Control ECU	Relief Valve	Returns the brake fluid to the reservoir to prevent excessive pressure if the pump operates continuously due to a malfunction of the accumulator pressure sensor.
	Solenoid Relay	Supply or cut off power to solenoid valves in the brake actuator.
	Motor Relay	Normally supplies power to the pump motor using two out of three relays. Ensures power to the pump motor by using the rest relay if the skid control ECU malfunctions.
	Linear Solenoid Valve	Controls the wheel cylinder pressure to generate a braking force responsive to the braking force requirement when the brake pedal is depressed normally.
	Switching Solenoid Valve	Switches the brake hydraulic path when the brake control system is activated.
	Control Solenoid Valve	Controls the wheel cylinder pressure when the ABS with EBD, BA, TRAC, VSC, hill-start control and Enhanced-VSC are activated.
	Regulator Pressure Sensor	The regulator pressure sensor converts the fluid pressure generated by the hydraulic brake booster into electrical signals and transmits them to the skid control ECU. Accordingly, the skid control ECU determines the braking force required by the driver.
	Wheel Cylinder Pressure Sensor	This sensor detects the fluid pressure that acts on the respective wheel cylinders and transmits them to the skid control ECU in the form of feedback. Accordingly, the skid control ECU monitors the fluid pressure of the wheel cylinders and controls the linear solenoid valve, in order to achieve the optimal wheel cylinder pressures.
	Accumulator Pressure Sensor	The accumulator pressure sensor constantly detects the brake fluid pressure in the accumulator and transmits the signals to the skid control ECU. Accordingly, the skid control ECU controls the pump motor.
Brake Booster Pump		Consisting of a pump, pump motor and accumulator, the hydraulic power source portion generates and stores the hydraulic pressure, which the skid control ECU uses for controlling braking. The relief valve is installed in the hydraulic brake booster. The accumulator pressure sensor is installed in the brake actuator.
Speed Sensor		Detects the wheel speed of each of four wheels.
Brake Pedal Stroke Sensor		Directly detects the extent of the brake pedal stroke operated by the driver.
Brake Fluid Level Warning Switch		Detects the low brake fluid level.
Skid Control Buzzer*1		Emits a warning sound to inform the driver during brake control operation (operating dynamic radar cruise control or pre-collision brake).
Stop Light Switch		Detects brake pedal operation.
Stop Light Control Relay		Illuminates the stop lights when hill-start assist control is operating.
Power Steering ECU		Operates cooperatively with the skid control ECU to control the steering assist torque.
Main Body ECU (Instrument Panel Junction Block)		Detects the parking brake signal and outputs it to the skid control ECU via CAN communication.
Power Management Control ECU		Actuates the regenerative brake on receiving signal from the skid control ECU. Sends the actual regenerative brake control value to the skid control ECU. Controls the motive force based on an output control request signal received from the skid control ECU while the VSC, TRAC or the dynamic radar cruise control system is operating.
Steering Angle Sensor		Detects the steering direction and angle of the steering wheel.
Yaw Rate and Acceleration Sensor		Detects the vehicles yaw rate. Detects the vehicles acceleration in the forward, rearward, and lateral.
Combination Meter	ABS Warning Light	Lights up to alert the driver when the skid control ECU detects the malfunction in the ABS, EBD, or BA.
	Brake Warning Light / Red (Malfunction)	Lights up to alert the driver when the skid control ECU detects the malfunction in the apportioning of the brake. Lights up to inform the driver when the parking brake is on or the brake fluid level is low.
	Brake Warning Light / Yellow (Minor Malfunction)	Lights up to alert the driver when a minor malfunction occurs in the brake system, which does not affect the braking force (such as a malfunction in the regenerative brake).
	Slip Indicator Light	Blinks to inform the driver when the ABS, the TRAC, the VSC or the hill-start assist control is operated. Lights up to alert the driver in the event of malfunction of the TRAC, VSC or hill-start assist control.
	Meter Buzzer	Emits a warning sound to inform the driver when hill-start assist control operation is started or finished. This buzzer sounds continuously to inform the driver when there is a malfunction in the hydraulic pressure or a failure in the power supply.

*1: w/ Dynamic Radar Cruise Control System