System Description

BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: SYSTEM DESCRIPTION

1. FUNCTION DESCRIPTION

(a) 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.

(b) 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 stability.

(c) 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 brake performance of the vehicle.

(d) TRAC (Traction Control)

The TRAC 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.

(e) 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.

2. ABS with EBD, BA, TRAC and VSC OPERATION

(a) The skid control ECU calculates vehicle stability tendency based on the signals from the speed sensor, yaw rate and acceleration sensor, and steering angle sensor. In addition, it evaluates the results of the calculations to determine whether any control actions (control of the engine output torque by electronic throttle control and of the wheel brake pressure by the brake actuator assembly) should be implemented.

(b) The Slip indicator blinks to inform the driver that the VSC system is operating. The Slip indicator also blinks when traction control is operating.

3. INITIAL CHECK

(a) When the vehicle speed first reaches approximately 6 km/h (4 mph) or more after the ignition switch is turned to ON, each solenoid valve and motor in the brake actuator is sequentially activated to perform an electrical check. During the initial check, the operating sound of the solenoid valves and motors can be heard from the engine compartment, but this is not a malfunction.

4. FUNCTION OF COMPONENTS