Vehicle Stability Assist (VSA)

ABS Features





When the brake pedal is pressed while driving, the wheels can lock before the vehicle comes to a stop. In such an event, the maneuverability of the vehicle is reduced if the front wheels are locked, and the stability of the vehicle is reduced if the rear wheels are locked, creating an extremely unstable condition. The ADS precisely controls the slip rate of the wheels to ensure maximum grip force from the tires, and it thereby ensures maneuverability and stability of the vehicle.
The ADS calculates the slip rate of the wheels based on the vehicle speed and the wheel speed, then it controls the brake fluid pressure to reach the target slip rate.

TCS Features





The TCS provides low speed traction. When a drive wheel loses traction on a slippery road surface and starts to spin, the VSA control unit sends a brake signal to the modulator unit, which applies brake pressure to slow the spinning wheel. At that time, the VSA control unit sends a traction control signal to reduce engine power.

VSA System Features
Oversteer control








- Applies the brake to the front outside tire
- Understeer control (in acceleration)
- Applies the brake to the front inside tire
- Cuts the engine torque by controlling the sub throttle

Self-Diagnosis





- The VSA control unit is equipped with a main CPU and a sub CPU. Each CPU checks the other for problems.
- The CPU checks the circuit of the system.
Self-diagnosis can be classified into two categories:
- Initial diagnosis: Done right after the engine starts and until the ABS or VSA system indicator goes off.
- Regular diagnosis: Done right after the initial diagnosis until the ignition switch is turned OFF.
- When a problem is detected by self-diagnosis, the VSA control unit shifts to fail-safe mode.