Description & Operation: Notes

When the brake pedal is pressed during 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. See Fig 1 .

Traction Control is a variable system designed to enhance traction during acceleration and cornering. It does so by determining the optimum amount of wheel spin for any given driving situation, then suppressing surplus engine power accordingly. This version of TCS has a lateral acceleration (Lg) sensor and a deceleration control function to improve traction control during acceleration and deceleration while cornering. When down shifting quickly to a very low gear on a slippery surface, the driving wheels tend to slip because of engine braking, resulting in lower directional stability. To counteract this, the deceleration control function controls engine braking with the ABS/TCS control unit.

The ABS/TCS control unit gets signals about the vehicles speed, direction, and road conditions from sensors at the wheels and the steering column. Based on these signals, the control unit will determine the optimum amount of wheel spin. Because the system is variable, the control unit may determine, depending on the driving conditions, that some wheel spin is beneficial (thus enhancing cornering). For any given driving situation, the control unit will determine the amount of wheel spin best suited to the driver's needs and, if necessary, will then signal the throttle actuator and Engine Control Module (ECM) to reduce engine power.

The system is automatically "ready" whenever the engine is started, but can be manually canceled with the TCS switch. However, once activated, the system cannot be canceled until it is once again in the ready state.