Hydraulic system and method for controlling pressure in a hydraulic system

A method for controlling pressure in a hydraulic system for a transmission of a vehicle with at least a primary friction element and a secondary friction element for coupling and transmitting engine power to wheels of the vehicle by actuation of the friction elements via the hydraulic system, the method comprising:

• supplying pressurized fluid to a line pressure circuit by means of a pressure pump system having at least two outlet lines;
• providing a bypass circuit on the pressure pump system that, when the bypass circuit is open to allow flow therethrough, a reduced pressure is obtained in one of the outlet lines;
• providing a primary operating element for controlling the pressure of the primary friction element via a primary valve;
• providing a line pressure operating element for controlling the line pressure via a line valve;
• providing a bypass operating element for controlling the bypass circuit via a bypass valve;
• wherein the bypass operating element additionally controls the secondary pressure on the secondary friction element via a secondary valve;
• such that in a determined state, when less torque is required on the friction elements;
• the bypass operating element is actuated to open the bypass circuit to reduce the flow to the line pressure circuit and additionally to reduce the secondary pressure on the secondary friction element to a value lower than the pressure on the primary friction element, such that less torque is provided.