A shifter abnormality diagnosis device for a shifter used in an automatic transmission having a manual mode, the shifter including a first switch for outputting a signal corresponding to the position of a select lever and a second switch for outputting a signal corresponding to the position of the select lever if the select lever is located in at least one of an upshift range or a downshift range, wherein the abnormality diagnosis device is configured to perform an abnormality diagnosis of the second switch on the basis of an output signal of the second switch and prohibit the abnormality diagnosis of the second switch if it is determined that the select lever is not located in any one of forward ranges including the upshift range and the downshift range on the basis of an output signal of the first switch.

A vehicle anomaly analysis apparatus for analyzing an anomaly having occurred in a shift control operation executed in an automatic transmission of a vehicle, by using a rotational speed changed in process of the shift control operation. The vehicle anomaly analysis apparatus specifies cause of the anomaly in the shift control operation, by applying an anomaly-cause specifying model that indicates a relationship between a manner of chronological change of a racing amount and the cause of the anomaly in the shift control operation, to the manner of the chronological change of the racing amount upon occurrence of the anomaly in the shift control operation. The racing amount is an amount of increase of the rotational speed in the process of the shift control operation, relative to a reference rotational speed that is based on a gear ratio and an output rotational speed of the automatic transmission.

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.

A method for controlling a valve to disengage a gear in a transmission. The method includes reducing, after receiving a request to disengage the gear, a current supplied to the valve from a starting to a first current. The method further includes counting a first elapsed time since the valve was reduced to the first current, comparing the first elapsed time to a first wait time, and increasing the current supplied to the valve to a second current once the first elapsed time exceeds the first wait time. The method further includes counting a second elapsed time since the valve was increased to the second current, comparing the second elapsed time to a second wait time, and reducing the current supplied to the valve to a third current once the second elapsed exceeds the second wait time. The valve is closed when the current is the third current.

A hydraulic system for an automatic transmission of a motor vehicle, with which hydraulic cylinders of at least one clutch and of gear selectors can be actuated, which hydraulic system has a pressure accumulator for providing an accumulator pressure in the hydraulic system, wherein a clutch valve that can be actuated by the control unit is arranged in a clutch path leading from the pressure accumulator to the clutch hydraulic cylinder.

A hydraulic system for an automatic transmission of a motor vehicle. A high-pressure circuit, in which a pressure accumulator, at least one clutch, and gear selectors and a hydraulic pump, which can be operated by an electronic control unit and by which the accumulator pressure in the high-pressure circuit can be increased in charging operation. A clutch valve that can be operated by the control unit is arranged in a clutch path between the pressure accumulator and a clutch hydraulic cylinder of the clutch, using which clutch valve a hydraulic pressure applied to the clutch hydraulic cylinder can be adjusted, and a safety valve that can be operated by the control unit is arranged upstream of the clutch valve.

An apparatus including a transmission mechanism in a power transfer path between a drive source and wheels; an oil pressure control device supplying lubricating oil to the transmission mechanism; and a control part outputting an electrical instruction to increase a flow rate of the supplied lubricating. When the control part outputs an electrical instruction to the oil pressure control device to increase a flow rate of lubricating oil supplied to the transmission mechanism, and determines that the flow rate of lubricating oil supplied to the transmission mechanism from the oil pressure control device does not increase as indicated by the electrical instruction (time t1), the control part considers that the oil pressure control device is in an abnormal state, and can impose a limitation that an absolute value of torque of the transmission mechanism transferred between the wheels and the drive source be reduced (time t1-t5).

A method is for testing a hydraulic system (1), having a pump (2) which, in a first direction of rotation (3), conveys fluid to a first consumer (4) for a volume flow function and, in a second direction of rotation (5), conveys fluid to at least one second consumer (6) for an actuation function. The method includes testing hydraulic readiness of the hydraulic system (1); drawing fluid into the hydraulic system (1); ventilating the hydraulic system (1). A hydraulic system (1) carries out such a method, having a pump (2) which can be driven in a first direction of rotation (3) for a volume flow function and can be driven in a second direction of rotation (5) for an actuation function.

A vehicle power transmission device includes: a continuously variable transmission including a primary pulley, a secondary pulley, and a transmission belt wound between the primary pulley and the secondary pulley; a belt running clutch of hydraulic type for transmitting power to the continuously variable transmission; and a hydraulic control circuit controlling the continuously variable transmission and the belt running clutch. The hydraulic control circuit includes a fail-safe valve switching a communication destination of an oil supply passage for supplying a hydraulic fluid to the belt running clutch to one of a first oil passage supplied with a control hydraulic pressure and a second oil passage supplied with a hydraulic pressure higher than the control hydraulic pressure, the fail-safe valve connecting the oil supply passage with the second oil passage when the fail-safe valve is switched to a failure position. The second oil passage is provided with an orifice.

Selection solenoid valve (75) controls engagement/disengagement of travel clutch (31, 32) in synchronization with a selecting operation of selector lever (90) that selects a range position of belt-type continuously variable transmission (CVT). Selection solenoid valve abnormality diagnosing unit (8a) is configured to, when performing a selecting operation from no-drive range to drive range, if a time required for travel clutch (31, 32) to be judged to be engaged from a start of selection of the drive range is less than a predetermined time, judge selection solenoid valve (75) to be a maximum hydraulic pressure side abnormality. When performing the selecting operation of drive range.fwdarw.no-drive range.fwdarw.drive range, if a selecting operation speed condition indicating that a no-drive range selection time is shorter than a setting time (Tth) is satisfied, execution of abnormality diagnosis of selection solenoid valve (75) is not permitted. With this configuration, misjudgment is prevented.