Vehicle Stability Control System System Description

  1. FUNCTION DESCRIPTION

  1. FUNCTION OF MAIN COMPONENTS

Vehicle Stability Control System -- System Description



FUNCTION DESCRIPTION

  1. ABS (Anti-lock Brake System)
    The ABS helps prevent the wheels from locking when the brakes are applied firmly or when braking on a slippery surface.

  2. EBD (Electronic Brake force Distribution)
    The EBD control utilizes ABS, and performs proper brake force distribution between the front and rear wheels in accordance with driving conditions.
    When braking while cornering, it also controls the brake forces of the right and left wheels, helping to maintain vehicle behavior.

  3. BA (Brake Assist)
    The primary purpose of the brake assist system is to provide auxiliary brake force to assist the driver if the driver cannot generate a large enough brake force during emergency braking, thus helping to maximize the braking performance of the vehicle.

  4. TRC (Traction Control)
    The TRC system helps prevent the drive wheels from slipping when the driver depresses the accelerator pedal excessively when starting off or when accelerating on a slippery surface.

  5. VSC (Vehicle Stability Control)
    The VSC system helps prevent the vehicle from slipping sideways as a result of strong front or rear wheel skid during cornering.


FUNCTION OF MAIN COMPONENTS

Component
Function
Brake warning light
  1. Lights up together with the ABS warning light to alert the driver when the skid control ECU detects an EBD control malfunction.
  2. Lights up to inform the driver when the parking brake is on.
ABS warning light
  1. Lights up to alert the driver when the skid control ECU detects a malfunction in the ABS or brake assist system.
  2. w/ Rear Differential Lock:
    When the rear differential lock is in the lock state, the ABS is also prohibited and the ABS warning light turns on.
Slip indicator light
  1. Blinks to inform the driver when the TRC or VSC system operates.
  2. Lights up when TRC or VSC is off.
VSC OFF indicator light
  1. Blinks to alert the driver when the skid control ECU detects a malfunction in TRC or VSC.
  2. Lights up when VSC is off.
Speed sensor
Detects the wheel speed of each of the four wheels.
Stop light switch
Detects the state of the brake pedal.
Parking brake switch
Detects the state of the parking brake.
VSC OFF switch
  1. Cancels TRC and VSC.
  2. Selects any of the three modes (Normal mode, TRC OFF mode, VSC OFF mode).
Brake actuator
Changes the fluid path based on signals from the skid control ECU during the operation of the ABS with EBD, brake assist, TRC and VSC in order to control the fluid pressure that is applied to the brake wheel cylinders.
Master cylinder pressure sensor
  1. Housed in the brake actuator.
  2. Detects the fluid pressure in the master cylinder.
Skid control ECU
  1. Housed in the brake actuator.
  2. Judges the vehicle driving conditions based on signals from each sensor, and sends a brake control signal to the actuator.
Motor relay
  1. Housed in the skid control ECU.
  2. Supplies power to the pump motor in the brake actuator.
Solenoid relay
  1. Housed in the skid control ECU.
  2. Supplies power to each solenoid.
Motor fail-safe relay
  1. Housed in the skid control ECU.
  2. Cuts the power to the pump motor in the brake actuator.
Yaw rate and acceleration sensor
  1. Detects the vehicle's yaw rate.
  2. Detects the vehicle's longitudinal and lateral acceleration and deceleration.
Steering angle sensor
  1. Installed in the spiral cable.
  2. Detects the steering direction and angle of the steering wheel.
ECM
  1. Sends the throttle valve angle signal, accelerator pedal position signal and engine speed signal to the skid control ECU.
  2. Receives the throttle control request signal from the skid control ECU.