A method of controlling a hydraulic circuit for a dual clutch transmission for motor vehicles, the hydraulic circuit comprising a first and a second hydraulically operable clutch (22, 24), the hydraulic circuit comprising a first and a second clutch circuit (32, 34), wherein the first clutch circuit has a first pressure control valve for controlling a first clutch pressure for the first clutch and wherein the second clutch circuit has a second pressure control valve for controlling a second clutch pressure for the second clutch, and wherein a safe state of the hydraulic circuit is ensured by means of a safety circuit (26, 46, 48, 50) in the event of a fault occurring, characterized in that the safety circuit (26, 46, 48, 50) is designed such that when a partial error occurs which is associated with only one of the two clutches (22, 24), this clutch is opened, and that when a total error occurs which is associated with both clutches (22, 24), the clutch whose clutch pressure is lower when the total error occurs is opened, and the other clutch whose clutch pressure is higher when the total error occurs is not opened in order to maintain the transmission of torque via this clutch, wherein the clutch circuits (32, 34) each include a release valve (42, 44) disposed between the pressure control valve (36, 38) and the clutch (22, 24) and adapted to close or disconnect the connection between the clutch (22, 24) and the associated pressure control valve (36, 38), wherein the release valves (42, 44), in the disconnected position, connect the clutch (22, 24) to a further valve arrangement (62, 64; 44', 42') adapted to connect the clutch (22, 24) to a tank or to a pressure holding device, depending on whether a partial or total failure has occurred, and wherein the pressure holding device comprises a pressure comparing device which compares the first and second clutch pressures (37, 39) with each other and, if a total error occurs, supplies the clutch with the higher clutch pressure with the holding pressure. the safety circuit (26, 46, 48, 50) is designed such that when a partial error occurs which is associated with only one of the two clutches (22, 24), this clutch is opened, and that when a total error occurs which is associated with both clutches (22, 24), the clutch whose clutch pressure is lower when the total error occurs is opened, and the other clutch whose clutch pressure is higher when the total error occurs is not opened in order to maintain the transmission of torque via this clutch, wherein the clutch circuits (32, 34) each include a release valve (42, 44) disposed between the pressure control valve (36, 38) and the clutch (22, 24) and adapted to close or disconnect the connection between the clutch (22, 24) and the associated pressure control valve (36, 38), wherein the release valves (42, 44), in the disconnected position, connect the clutch (22, 24) to a further valve arrangement (62, 64; 44', 42') adapted to connect the clutch (22, 24) to a tank or to a pressure holding device, depending on whether a partial or total failure has occurred, and wherein the pressure holding device comprises a pressure comparing device which compares the first and second clutch pressures (37, 39) with each other and, if a total error occurs, supplies the clutch with the higher clutch pressure with the holding pressure.