Brake control system for a vehicle

A brake control system for a vehicle comprising:

• wheel brake cylinders operatively mounted on front and rear wheels of said vehicle, respectively;
• a master cylinder for pressurizing brake fluid to supply hydraulic braking pressure to said wheel brake cylinders in response to depression of a brake pedal;
• a pair of main passages for communicating said master cylinder with said wheel brake cylinders to provide a dual hydraulic pressure circuit system;
• an auxiliary pressure source for pressurizing the brake fluid to supply the hydraulic braking pressure to said main passages;
• wheel speed sensors for detecting wheel speeds of said wheels;
• slip calculation means for calculating slip of said wheels on the basis of the wheel speeds detected by said wheel speed sensors;
• and
• control means for comparing the slip of at least one of said front wheels with the slip of at least one of the wheels belonging to a hydraulic pressure circuit different from the hydraulic pressure circuit to which said at least one of said front wheels belongs, and for applying the hydraulic braking pressure discharged from said auxiliary pressure source to said wheel brake cylinder operatively mounted on said at least one of said front wheels, in the case where the slip of said at least one of said front wheels is smaller than the slip of said at least one of said wheels belonging to a different hydraulic pressure circuit from the hydraulic pressure circuit to which said at least one of said front wheels belongs, at least when said brake pedal is being operated.