A fault evaluation device for an automatic transmission evaluates a fault of the automatic transmission. The fault evaluation device is used for a vehicle having the automatic transmission and a control device configured to execute a learning process for correcting a target pressure for oil to be supplied to the automatic transmission such that variations in acceleration of the vehicle during shifting of the automatic transmission are small. The fault evaluation device includes a processor and a memory. The memory stores mapping data that prescribe mapping. The processor is configured to output an output variable, which is an evaluation value that indicates the presence or absence of the fault of the automatic transmission, when an input variable is input.

An abnormality cause determining device that is applied to a vehicle including an electromagnetic actuator includes a storage device and an execution device. The storage device is configured to store map data which is data for defining a map. The map includes a current variable which is a variable indicating a current flowing actually in the electromagnetic actuator as an input variable and includes a cause variable which is a variable indicating a cause of an abnormality of an onboard unit including the electromagnetic actuator as an output variable. The execution device is configured to perform an acquisition process of acquiring a value of the input variable based on a detection value from a sensor which is mounted in the vehicle and a calculation process of calculating a value of the output variable by inputting the value of the input variable to the map.

A control device provided in a gear shifting device includes an electronic control unit. The electronic control unit determines whether an abnormality of the gear shifting device has occurred, performs a fail-safe process of switching the frictional engagement element corresponding to an abnormality to a disengaged state and fixing the gear shift ratio of the gear shifting device when it is determined that an abnormality has occurred, determines whether the abnormality has been relieved based on a behavior of an input signal at the time of operating a drive device of the frictional engagement element corresponding to an abnormality on condition that the frictional engagement element is maintained in the disengaged state after it is determined that the abnormality has occurred, and releases the fail-safe process when it is determined that the abnormality has been relieved.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A hydraulic system for an automatic transmission of a motor vehicle, including a high pressure circuit in which a pressure accumulator, at least one clutch and a gear selector are connected, and comprising a low pressure circuit for cooling the clutch, wherein the high pressure circuit and the low pressure circuit have at least one hydraulic pump that can be driven by an electric motor, and including a control unit that actuates the electric motor of the hydraulic pump when a pressure accumulator charging requirement is detected, wherein the high and low pressure circuits are connected via a bypass line to an integrated accumulator charging valve.

The invention relates to an arrangement for reading off predetermined positions of a gear lever (11). A sensor arrangement (1) with a first sensor component (10) moves with the gear lever (11) and a plurality of second sensor components (S21-S25) interacts with the first sensor component (10), wherein in each of the predetermined positions of the gear lever (11), the first sensor component (10) interacts with at least one second sensor component (S21-S25). A position determination unit (30) compares the current sensor output values with stored sensor output values in a table (40). When a faulty condition is detected in one of the sensor components (S21-S25), the stored sensor output values for the faulty sensor component are updated with the faulty output value of the faulty sensor component in the table (40) of expected sensor output values.

Systems and methods are provided for controlling a transmission. An engine stop-start event may be allowed or denied based on one or more characteristics of the vehicle including the transmission.

A hydraulic system for an automatic transmission of a motor vehicle. A high pressure circuit in which a pressure accumulator, at least one clutch as well as gear selectors and at least one hydraulic pump are arranged, which can be controlled by an electronic control unit. The pressure accumulator can be connected to a hydraulic positioning cylinder via at least one hydraulic path, wherein a control valve that can be controlled by the control unit is arranged upstream thereof, with which a hydraulic pressure at the hydraulic positioning cylinder can be adjusted, and which control valve can be moved between two through-flow positions in order to move a piston in opposing piston strokes via opposing piston travel paths as well as piston speeds in the hydraulic positioning cylinder.

A valve system for a hydraulic emergency driving gear function of a hydraulic control unit for a motor vehicle automatic transmission includes a position valve (104) with a first piston slide (120) and an electromagnetic pressure regulator (86) having a decreasing characteristic curve. The first piston slide (120) is preloaded in a first position. When the first piston slide (120) is in a second position, the electromagnetic pressure regulator (86) is configured for connecting a system pressure-carrying line (18) of the motor vehicle automatic transmission to a first emergency driving gear clutch (12) of the motor vehicle automatic transmission and to a second emergency driving gear clutch (15) of the motor vehicle automatic transmission, whereby the first emergency driving gear clutch (12) and the second emergency driving gear clutch (15) are actuated, so that an emergency driving gear of the motor vehicle automatic transmission is engaged.

A diagnosis device determines diagnoses one of primary and secondary board temperature sensors as abnormal, in response to a condition that a state in which a primary temperature sensor value and a secondary temperature sensor value deviate from each other by a predetermined value or more continues for a predetermined duration or more; performs torque limitation to limit a torque inputted from an engine to an automatic transmission, during driving in a predetermined travel section based on a predetermined condition, after the one of the primary and secondary board temperature sensors is diagnosed as abnormal; and performs transmission shift restriction to restrict shifting of the automatic transmission along with the torque limitation, in response to a condition that the one of the primary and secondary board temperature sensors continues to be diagnosed as still abnormal after the driving in the predetermined travel section is completed.