A vehicle transmission includes a plurality of friction clutches and a selectable one-way clutch. The transmission also includes a controller programmed to, in response to detecting a component fault, switch the selectable one-way clutch from a passive state to an active state by commanding engagement of a first subset of the friction clutches to establish a slip elimination state. The controller is also programmed to, following establishment of the slip elimination state, command the selectable one-way clutch to the active state.

In a hybrid vehicle, a hybrid type lubrication control valve which is a solenoid valve type turned on/off by electricity is used as a lubrication system component for circulating lubricating oil to a transmission and an engine clutch. A method includes measuring, by an engine clutch pressure sensor, first engine clutch engagement pressure in an off-state of the independent type lubrication control valve and second engine clutch engagement pressure in an on-state thereof; and determining, by the TCU, whether or not the independent type lubrication control valve is stuck, on the basis of a pressure difference between the first engine clutch engagement pressure and the second engine clutch engagement pressure. The method can diagnose a stuck state of the hybrid type lubrication control valve using hydraulic pressure for operating engine clutch engagement, before starting the vehicle.

A control apparatus for a vehicle drive-force transmitting apparatus including a dog clutch that is operated by an actuator to selectively connect and disconnect a drive-force transmitting path. In process of switching of the dog clutch from released state to engaged state, the control apparatus determines whether a rotational speed difference of the dog clutch is equal to or larger than a given difference value when a sleeve of the dog clutch is positioned on an engaging side of a synchronizing position for placing the dog clutch into the engaged state, and stops the switching of the dog clutch to the engaged state and causes the actuator to place the dog clutch back into the released state, when determining that the rotational speed difference is equal to or larger than the given difference value with the sleeve being positioned on the engaging side of the synchronizing position.

A rotational system can include a shaft assembly rotationally coupling a first rotor, a second rotor, and a fluid pump. A fluid circuit can include the fluid pump that can be configured to motivate a working fluid through the fluid circuit. A pressurizing valve can be disposed downstream of the fluid pump wherein the rotational system can be configured to rotationally decouple the first rotor from the second rotor by closing the pressurizing valve. The pressurizing valve can be actuated by a controller. A method can include raising a pressure differential across a fluid pump driven by a shaft assembly thereby applying an increased braking torque to the shaft assembly. The pressure differential can be raised by actuating a valve in hydraulic communication with the fluid pump. The shaft assembly can rotationally couple a first rotor with a second rotor, and increasing the braking torque can decouple the rotors.

Power transmission systems including clutch arrangement and control systems are adapted to be used in numerous different operational environments. Such power transmission systems may include clutch arrangements that provide more effective power transmission capabilities as well as greater durability and longer life. Control arrangements are provided to more effectively control and monitor clutch operation in ways that provide for greater system flexibility and drive options.

In a hybrid vehicle, a hybrid type lubrication control valve which is a solenoid valve type turned on/off by electricity is used as a lubrication system component for circulating lubricating oil to a transmission and an engine clutch. A method includes measuring, by an engine clutch pressure sensor, first engine clutch engagement pressure in an off-state of the independent type lubrication control valve and second engine clutch engagement pressure in an on-state thereof; and determining, by the TCU, whether or not the independent type lubrication control valve is stuck, on the basis of a pressure difference between the first engine clutch engagement pressure and the second engine clutch engagement pressure. The method can diagnose a stuck state of the hybrid type lubrication control valve using hydraulic pressure for operating engine clutch engagement, before starting the vehicle.

A clutch controller provides protective disengagement of a clutch between an engine and driven machinery to prevent engine failure due to rapid onset overload. Sensor signals of measured parameters are used by the controller to determine potential engine failure. Multiple, successive sensor signals and elapsed times are assessed during which the current sensor signal value and the scaled rate of change in signal values is compared against a predefined amount. The clutch controller sends a clutch disengagement signal if a calculation result is indicative of imminent failure.

A rotational system can include a shaft assembly rotationally coupling a first rotor, a second rotor, and a fluid pump. A fluid circuit can include the fluid pump that can be configured to motivate a working fluid through the fluid circuit. A pressurizing valve can be disposed downstream of the fluid pump wherein the rotational system can be configured to rotationally decouple the first rotor from the second rotor by closing the pressurizing valve. The pressurizing valve can be actuated by a controller. A method can include raising a pressure differential across a fluid pump driven by a shaft assembly thereby applying an increased braking torque to the shaft assembly. The pressure differential can be raised by actuating a valve in hydraulic communication with the fluid pump. The shaft assembly can rotationally couple a first rotor with a second rotor, and increasing the braking torque can decouple the rotors.

A method of, and a system for, controlling and predicting the health of a torque converter clutch control system is provided. The method includes determining, via a controller, rotational input and output speeds of the torque converter and a torque converter clutch slip. The method also includes determining, via the controller, whether a set of predetermined conditions are met for predicting the health of the torque converter clutch control system. The method includes gathering a plurality of initial features of the vehicle propulsion system, determining statistical information about the plurality of initial features, and selecting at least one feature of the vehicle propulsion system based on the statistical information. Furthermore, the method includes classifying the health of the torque converter clutch control system based on the selected feature or features. In some forms, principal component analysis is used to select the feature or features used for classification.

A vehicle transmission includes a plurality of friction clutches and a selectable one-way clutch. The transmission also includes a controller programmed to, in response to detecting a component fault, switch the selectable one-way clutch from a passive state to an active state by commanding engagement of a first subset of the friction clutches to establish a slip elimination state. The controller is also programmed to, following establishment of the slip elimination state, command the selectable one-way clutch to the active state.