A transmission for a machine is disclosed. The transmission may comprise a torque path providing a path for transmission of torque from an input shaft to an output shaft, and a single clutch element along the torque path. The transmission may further comprise a clutch actuator configured to actuate engagement of the clutch element, and a clutch pressure control (CPC) valve configured to permit a flow of hydraulic fluid to the clutch actuator through a control pressure line when in an open position to cause the clutch actuator to actuate engagement of the clutch element. The transmission may further comprise a failure mode response (FMR) valve in the control pressure line between the CPC valve and the clutch actuator. The FMR valve may have a failure position obstructing flow of the hydraulic fluid from the CPC valve to the clutch actuator when the CPC valve is in the open position.

A vehicle control device is applied to a vehicle including at least a shift control system configured to switch a shift range. The vehicle control device is configured to control the vehicle to perform autonomous driving travel without depending on an operation of a driver in at least one driving operation. The vehicle control device includes a controller. The controller is configured to determine the propriety of travel by the autonomous driving travel according to a type of abnormality that occurs in the shift control system. The controller is configured to perform travel control of the vehicle according to the propriety of the travel by the autonomous driving travel.

A transmission for a machine is disclosed. The transmission may comprise a torque path providing a path for transmission of torque from an input shaft to an output shaft, and a single clutch element along the torque path. The transmission may further comprise a clutch actuator configured to actuate engagement of the clutch element, and a clutch pressure control (CPC) valve configured to permit a flow of hydraulic fluid to the clutch actuator through a control pressure line when in an open position to cause the clutch actuator to actuate engagement of the clutch element. The transmission may further comprise a failure mode response (FMR) valve in the control pressure line between the CPC valve and the clutch actuator. The FMR valve may have a failure position obstructing flow of the hydraulic fluid from the CPC valve to the clutch actuator when the CPC valve is in the open position.

A method for operating a pneumatic actuating system of a transmission. The actuating system has an air reservoir at a first pressure. The reservoir couples an actuating space of the actuating system which is at a second pressure, and the actuating space couples, via control valves, shifting cylinders. When conducting a transmission gearshift, an air mass delivered to the active shifting cylinders via corresponding control valves, and an air mass sum including a nominal air mass in the active cylinders required for accomplishing the gearshift and an actual basic leakage from the activated shifting cylinder are determined. A defect leak in the pneumatic actuating system is recognized, if the air mass delivered to the active shifting cylinders is larger than the air mass sum. If a defect leak is recognized, the control valves coupling the actuating space and the shifting cylinders are shut off for a period of time.

A back-up control unit of a back-up power source device executes: a battery failure determination process of determining whether or not a battery failure has been detected by a failure detecting unit; when it is determined that battery failure has been detected in the battery failure determination process, a switching instruction determination process for determining, on the basis of an instruction signal from a monitor circuit, whether or not an instruction to switch to a P range has been made by a user; and when it is determined that a switching instruction has been made in the switching instruction determination process, a shifting instruction process for starting power supply from a back-up power source to a shift control unit and instructing the shift control unit to shift to the P range.

A vehicle control device controls a vehicle control system, which includes a shift range switching system configured to switch a shift range by controlling a drive of a shift actuator, and an electric brake system configured to brake a vehicle by controlling a drive of a brake actuator. The vehicle control device includes a shift control unit and a brake control unit. The shift control unit controls a drive of the shift actuator. The brake control units control a drive of a brake actuator. When the start switch of the vehicle is turned off, the power of the brake control units is turned off after the shift range switching system completes switching to the P range.

A vehicle control device controls a vehicle control system, which includes a shift range switching system configured to switch a shift range by controlling a drive of a shift actuator, and an electric brake system configured to brake a vehicle by controlling a drive of a brake actuator. The vehicle control device includes a drive control unit, an abnormality monitoring unit, and a presence determination unit. The drive control unit controls a drive of a shift actuator. The abnormality monitoring unit monitors an abnormality of the shift range switching system. The presence determination unit determines whether the driver is in the driver's seat. When the abnormality of the range mismatch, which the actual shift range does not match the target shift range in a state where the driver is absent, the vehicle control device executes the fail safe process different from the fail safe process when the driver is present.

In a transmission control device, a controller determines failure of one of a variator input side rotation sensor and a variator output side rotation sensor. A hydraulic control circuit and the controller variably control line pressure, and in a case where the failure is determined, fix the line pressure to a predetermined value or more. The hydraulic control circuit and the controller variably control a speed ratio of a variator by a double pressure regulation method, and in a case where the failure is determined, variably control the speed ratio of the variator by a single pressure regulation method.

In a transmission control device for controlling a transmission, a controller determines failure of a specific section. The controller variably controls line command pressure and secondary command pressure, and in a case where the failure is determined, fixes the line command pressure to a line pressure set value and the secondary command pressure to a secondary pressure set value. In a case where the failure is determined, the controller further starts a change in the secondary command pressure after start of a change in the line command pressure, and controls the secondary command pressure in such a manner that the secondary command pressure takes a first predetermined time to have the secondary pressure set value.

A controller of a power transmission system for a vehicle includes an electronic control unit. When a difference between a secondary pressure set by use of a command pressure of the electromagnetic control valve for the secondary pulley, and an actual pressure obtained by a hydraulic pressure sensor, is larger than a predetermined pressure difference, the electronic control sets a primary pressure and the secondary pressure such that a speed ratio of a continuously variable transmission becomes substantially equal to a maximum value. The electronic control unit determines that there is an abnormality that an output pressure of the electromagnetic control valve for a secondary pulley is low, when the speed ratio is smaller than a predetermined first determination value, and determines that there is an abnormality in the hydraulic pressure sensor, when the speed ratio is larger than a predetermined second determination value.