Brake system for a vehicle and method of operating a brake system of a vehicle

The present invention provides a brake system for a vehicle comprising a first master cylinder (50) with at least a first pressure chamber (52) and a first piston (54), which is movable at least partially into the first pressure chamber (52) by a braking force applied on a brake actuation element, a first brake circuit (62) with at least one first wheel brake cylinder (64), and a second brake circuit (68) with at least one second wheel brake cylinder (70), wherein the second brake circuit (68) is tied to a second pressure chamber (72) of a second master cylinder (74) comprising the second pressure chamber (72), a pre-chamber (76) and a second piston (78) separating the second pressure chamber (72) from the pre-chamber (76), and wherein the pre-chamber (76) is hydraulically connected to the first pressure chamber (52) via a hydraulic line (80). The present invention also relates to a method of operating a brake system of a vehicle having seperate master cylinders and a booster pump (94)in the second brake circuit (68) for generating a hydraulic pressure in the at least one second wheel brake cylinder (70) independently of a hydraulic pressure being generated in the first pressure chamber (52).