Apparatus and method for a hydraulic brake system including manual push-through

A brake system for hydraulically actuating a pair of front wheel brakes and a pair of rear wheel brakes, the system having normal non-failure, manual push-through, and backup braking modes, the system comprising:

• a reservoir;
• a master cylinder fluidly connected to the reservoir and operable to provide a brake signal responsive to actuation of a brake pedal connected thereto, the master cylinder being selectively operable during the manual push-through mode by actuation of the brake pedal to generate brake actuating pressure at an output for hydraulically actuating at least one brake of the pair of front wheel brakes;
• a first power transmission unit, in fluid communication with the reservoir, a selected one of the rear wheel brakes, and a first fluid separator corresponding to a selected one of the front wheel brakes, the first power transmission unit being configured to selectively generate pressurized hydraulic fluid for actuating the selected one of the front wheel brakes during a normal non-failure braking mode;
• a first electronic control unit configured to control the first power transmission unit;
• a second power transmission unit, in fluid communication with the reservoir, the other one of the rear wheel brakes, and a second fluid separator corresponding to an other one of the front wheel brakes, the second power transmission unit being configured to selectively generate pressurized hydraulic fluid for actuating the other one of the front wheel brakes during a normal non-failure braking mode;
• and
• a second electronic control unit configured to control the second power transmission unit, wherein the first and second fluid separators are positioned in fluid paths between the master cylinder and the respective front wheel brakes.