Understanding Electronic Stability Control


Technically speaking, stability control is a computer-controlled system that regulates hydraulic and mechanical components on the vehicle using sensors shared with the anti-lock braking system (ABS) and traction control system (TCS). With a typical stability control system, the ABSand TCS sensors monitor the speed of each wheel. Additional sensors monitor the vehicle speed, steering wheel angles, and yaw (how the car turns on its vertical axis). During normal driving, all of the sensors report vehicle data to a high-speed microcomputer. By comparing the steering wheel angle to the vehicle readings, the microcomputer is able to determine if the driver has the vehicle under control, or has entered an unstable situation (a skid or uncontrolled slide, for example).

If the stability control system determines the vehicle is experiencing a potential loss of direction, it immediately attempts to correct the problem by controlling the throttle and braking in an attempt to bring the vehicle under control (it does not control the steering wheel). In operation, the stability control system is far more capable than any driver. Not only does it respond faster, but it is able to control each wheel independently-a feat that is impossible from behind the steering wheel.

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