Method for adjusting brake pressures of a vehicle, and brake system for carrying out the method

A braking system of a motor vehicle or a vehicle combination including a motor vehicle as the towing vehicle and at least one towed vehicle, the braking system comprising:

• an antilock braking system comprising a brake control unit,
• at least one driver assistance system,
• the braking system further comprising, per wheel:
• one brake cylinder and one pressure control valve, which are connected to the brake control unit in a signal-transmitting manner in order to receive control signals during a pressure control mode,
• a service-brake valve which can be actuated by a driver of the vehicle, and
• a brake signal emitter,
• wherein brake pressures in the brake cylinders are adjustable by the brake control unit, in a normal braking mode, depending on a driver's braking demand, by actuating the service-brake valve and, in a pressure-control mode, via the particular pressure control valve,
• wherein the brake control unit is designed for receiving demanded vehicle decelerations via braking demands from the at least one driver assistance system and is connected to speed sensors of the wheels for detecting the rotational behavior and for monitoring a tendency of the wheels of the vehicle to lock on the basis of the measuring signals of the speed sensors and, upon determination of a tendency of at least one wheel to lock and/or upon reception of a demanded vehicle deceleration, takes over the adjustment of the brake pressures in the pressure control mode, and
• wherein the brake control unit is configured for continuously determining differential slip values from the measuring signals of the speed sensors as the difference between the slip of two axles of the vehicle and for evaluating and readjusting the differential slip value according to one predefined or ascertained setpoint differential slip value by adapting the control signals.