Brake system and method for operating same

A method of operating a brake system of a motor vehicle having a hydraulic system providing pressure to a front wheel brake and rear wheel brake and a parking brake system including the steps of:

• carrying out autonomous emergency braking of the motor vehicle by actuating the hydraulic system via an electronic brake control in such a manner that a brake pressure is built up by the hydraulic system, wherein at the beginning of the autonomous emergency braking valves of the hydraulic system associated with the rear wheel brakes are closed and valves of the hydraulic system associated with the front wheel brakes are opened;
• and
• activating the parking brake system wherein the valves of the hydraulic system associated with the rear wheel brakes are kept closed for a period of adjustable length;
• detecting a load condition of the motor vehicle;
• comparing the detected load condition of the motor vehicle with a predetermined load condition limit value necessary to carry out autonomous emergency braking of the motor vehicle;
• and
• if the detected load condition of the motor vehicle is lower than the load condition limit value the valves of the hydraulic system associated with the rear wheel brakes and the front wheel brakes are opened without activating the parking brake system.

A method of operating a motor vehicle brake system comprising:

• providing a hydraulic system for supplying pressure to a front wheel brake and rear wheel brake;
• providing a parking brake;
• supplying pressure to a front wheel brake;
• activating the parking brake;
• withholding pressure to the rear wheel brake for a period of adjustable length;
• and
• deactivating the parking brake and supplying pressure to the rear wheel brake after the period of adjustable length has elapsed.

A method of operating a motor vehicle brake system comprising:

• providing a hydraulic system for supplying pressure to a front wheel brake and rear wheel brake;
• providing a parking brake;
• supplying pressure to a front wheel brake;
• activating the parking brake;
• withholding pressure to a rear wheel brake;
• detecting a load condition of the motor vehicle;
• comparing the detected load condition of the motor vehicle with a predetermined load condition limit value;
• if the detected load condition of the motor vehicle is lower than the load condition limit value skipping the steps of activating the parking brake and withholding pressure to the rear wheel brake;
• and
• supplying pressure to the rear wheel brake.