Hydraulic control apparatus for an automatic dual clutch transmission

A method for controlling a dual clutch transmission using a hydraulic control apparatus for an automatic dual clutch transmission, including the method steps:

• providing a first clutch with a first partial transmission and a second clutch with a second partial transmission, as well as a shifting system for engaging/disengaging gears of the two partial transmissions
• providing a control unit;
• controlling by means of said control unit at least one of the parameters of controllable pressure and controllable volumetric flow for the actuation of the first and second clutches and for the actuation of the shifting system, and
• providing a switching apparatus that is arranged between the control unit and the clutches or the shifting system and can be used to switch the controllable pressure or the controllable volumetric flow between the clutches or the shifting system, the control unit having a first pressure regulator and a second pressure regulator, and the switching apparatus having a first changeover valve and a second changeover valve,
• operating the first changeover valve in such a manner that the first changeover valve
• a) in a first position (AI) connects the first pressure regulator to the first clutch and disconnects the first pressure regulator from the shifting system, and
• b) in a second position (BI) connects the first pressure regulator to the shifting system and disconnects the first pressure regulator from the first clutch;
• and
• operating the second changeover valve in such a manner that the second changeover valve
• c) in a first position (AII) connects the second pressure regulator to the second clutch and disconnects the second pressure regulator from the shifting system, and
• d) in a second position (BII) connects the second pressure regulator to the shifting system and disconnects the second pressure regulator from the second clutch,
• shifting in case of failure of the first pressure regulator the first changeover valve to its second position (BI) and the second changeover valve to its second position (BII).