A method for automatically warming up a clutch actuator for a clutch of a transmission in a vehicle, wherein the clutch actuator is operable by use of pressurized fluid and configured to actuate the clutch from an engaged to a disengaged state, and/or vice versa, the method including: identifying if a temperature is below a predetermined temperature value and if the clutch actuator is leaking, and if it is identified that the temperature is below the predetermined temperature value and that the clutch actuator is leaking; then repeatedly pressurizing the clutch actuator by use of the pressurized fluid until a state is reached indicative of the clutch actuator being functional, or until a maximum run out state is reached indicative of a faulty clutch actuator.

A method for automatically warming up a clutch actuator for a clutch of a transmission in a vehicle, wherein the clutch actuator is operable by use of pressurized fluid and configured to actuate the clutch from an engaged to a disengaged state, and/or vice versa, the method including: identifying if a temperature is below a predetermined temperature value and if the clutch actuator is leaking, and if it is identified that the temperature is below the predetermined temperature value and that the clutch actuator is leaking; then repeatedly pressurizing the clutch actuator by use of the pressurized fluid until a state is reached indicative of the clutch actuator being functional, or until a maximum run out state is reached indicative of a faulty clutch actuator.

A method for controlling a hydraulic system for actuating a drive train device of a drive train of a motor vehicle includes a first volumetric flow a pressure medium being provided by an electrically operated pump, and a slave cylinder piston of a slave cylinder being actuated along an actuation path, in a manner controlled by a switch valve, via a second volumetric flow generated from the first volumetric flow. A leakage in the hydraulic system is determined from a comparison of the first and second two volumetric flows.

A method for controlling a pneumatic actuator (1) of a transmission having at least one sealing element (6, 7) that is arranged between two elements (2, 3) of the actuator (1) that move relative to one another, and within a specifiable operating temperature range in which a leakproofness of the actuator (1) is ensured. The pneumatic actuator is acted upon with compressed air from an air supply system for actuating a transmission component. When a temperature of the actuator (1) is below a glass transition temperature of the at least one sealing element (6, 7), the actuator (1) is acted upon with pre-heated compressed air from the air supply system to warm up the at least one sealing element (6, 7) above the glass transition temperature.

The present disclosure provides a method of diagnosing an oil leak of an engine clutch in a hybrid electric vehicle including: when the engine starts up in the hybrid electric vehicle, operating a hydraulic actuator provided in the engine clutch, wherein the hydraulic actuator is configured to perform engagement or disengagement between an engine and a motor; determining displacement of a piston provided in the hydraulic actuator and pressure for any displacement of a plurality of the displacements of the piston; calculating a pressure gradient based on the displacement of the piston and the pressure for any displacement of the plurality of the displacements of the piston; and determining the oil leak of the engine clutch based on the pressure gradient.

An apparatus for determining a failure of an engine clutch is provided. The apparatus includes an engine clutch that is disposed between an engine generating power and a motor and a driving information detector that senses driving information including a shift speed stage, an engine speed, a motor speed, a SOC of a battery, and a vehicle speed. A controller then determines a driving mode of the engine from the detected driving information and determines whether oil leakage of the engine clutch is generated from the driving information and the driving mode.

A method for stabilizing an engine clutch control includes transmitting an engine clutch operation start command from a controller to an engine clutch system, the engine clutch system including an engine clutch, detecting a hydraulic pressure generated during the operation of the engine clutch system, carrying out an oil leakage judgment mode using the controller to determine whether the hydraulic pressure is a normal hydraulic pressure where the operation of the engine clutch is available or if the hydraulic pressure an abnormal hydraulic pressure where the operation of the engine clutch is unavailable, and changing an operation mode to an emergency operation mode wherein the operation of the engine clutch is stopped in case of abnormal hydraulic pressure, and carrying out an operation mode change by operating the engine clutch in a case of normal hydraulic pressure, based on a control by the controller.

A method for controlling a pneumatic actuator (1) of a transmission having at least one sealing element (6, 7) that is arranged between two elements (2, 3) of the actuator (1) that move relative to one another, and within a specifiable operating temperature range in which a leakproofness of the actuator (1) is ensured. The pneumatic actuator is acted upon with compressed air from an air supply system for actuating a transmission component. When a temperature of the actuator (1) is below a glass transition temperature of the at least one sealing element (6, 7), the actuator (1) is acted upon with pre-heated compressed air from the air supply system to warm up the at least one sealing element (6, 7) above the glass transition temperature.

The integrated controller determines whether or not, regardless of execution of the WSC control, a rotation speed of the motor generator falls to less than an idle rotation speed and also whether or not differential rotation of the second clutch becomes less than a predetermined value, and determines that, if the determination is positive, a continuous MAX pressure failure has occurred in the second clutch.

A method for controlling a hydraulic system for actuating a drive train device of a drive train of a motor vehicle includes a first volumetric flow of a pressure medium being provided by an electrically operated pump, and a slave cylinder piston of a slave cylinder being actuated along an actuation path, in a manner controlled by a switch valve, via a second volumetric flow generated from the first volumetric flow. A leakage in the hydraulic system is determined from a comparison of the first and second volumetric flows.