Method for estimating master cylinder pressure during brake apply

A method for estimating master cylinder pressure during brake apply of a brake system of a vehicle, wherein the brake system includes a brake pedal, and wherein the method comprises:

• a) determining a first master cylinder pressure from brake pedal position during brake apply;
• b) determining a second master cylinder pressure from vehicle deceleration during brake apply;
• c) estimating the master cylinder pressure during brake apply to be equal to the first master cylinder pressure when the vehicle deceleration is below a predetermined deceleration value;
• d) calculating an error to be equal to the first master cylinder pressure minus the second master cylinder pressure when the vehicle deceleration is at or above the predetermined deceleration value;
• e) estimating the master cylinder pressure during brake apply to be equal to the first master cylinder pressure minus a value of a variable percentage of the error when the vehicle deceleration is at or above the predetermined deceleration value, wherein the value of the variable percentage is adaptively learned over time;
• and
• f) using at least the estimated master cylinder pressure during brake apply to control the vehicle.