US Patent 10124783 Brake circuit leak detection and isolation

A method for detecting the location of and isolating a leak in a braking system by simultaneously controlling a direct apply subsystem (DAS) and an isolated apply subsystem (IAS) to enable fluid communication between the IAS and the first circuit; to block fluid communication of the DAS with the first circuit; to enable fluid communication of the DAS with the second circuit; and to block fluid communication of the IAS with the second circuit. A sensed travel of an isolated apply component and a sensed fluid pressure developed by the IAS may be used to determine if the leak is present in the first circuit, while simultaneously using the sensed travel of a direct apply component of the DAS, and a sensed fluid pressure developed by the DAS, to determine if the leak is present in the second circuit.