Electronic Skid Control System: Operation: Notes

Skid control begins as speed indication impulse (electrical frequency proportional to wheel speed) is sent from sensor to controller. When wheel is not locking during brake application, wheel will gradually decelerate. If wheel starts to lock, wheel will decelerate faster than vehicle speed. Controller determines that frequency is changing rapidly and that vehicle is approaching skid condition. Controller sends an electrical impulse to modulator solenoid. Solenoid will create a sealed hydraulic circuit between master cylinder and rear wheel cylinders. Fluid volume from modulator to rear wheel cylinders is increased, causing partial brake release, eliminating skid possibility. Wheels accelerate and as vehicle speed is approached, controller senses condition and modulator solenoid is de-energized. Brake pressure is increased to wheel cylinders and modulator is positioned until a skid condition is sensed again. During a skid condition, system will continue to cycle until vehicle slows to approximately five miles per hour or until brakes are released.