Abstract: A control apparatus for an automatic transmission including a plurality of frictional elements each arranged to be engaged by receiving supply of an engagement pressure regulated by a solenoid, and being arranged to attain a plurality of gear stages by combination of engagements of the frictional elements, the control apparatus includes a failure occurrence sensing section configured to sense an occurrence of a failure-induced disengagement in one of the frictional elements based on a failure of one of the solenoids, based on an engine racing by a depression of an accelerator pedal in a state in which ranges other than a parking range and a neutral range are selected during a stop of a vehicle; and a command output section configured to output a limp home mode command to attain one of the gear stages to enable the vehicle to start.

Abstract: In vehicular control method and apparatus for a shift-by-wire device, a selected shift position is modified to at least one of a vehicular parking position, a neutral position, and a traveling position, the selected shift position is modified to the vehicular parking position when a power switch is switched to an OFF position, and the modification of the shift position to the vehicular parking position is inhibited when an operation pattern of an operation input section while the power switch is in the ON position is made coincident with the operation pattern prescribed as a cipher code which inhibits the shift position modification to the vehicular parking position, the operation patterns being constituted by a combination of operation patterns which would not be carried out in the operation section during an ordinary traveling.

Abstract: An automatic transmission system includes a transmission having transmission elements with lubrication-requiring portions and hydraulic actuators therefor, a switching valve that supplies hydraulic fluid to the hydraulic actuators, a valve actuator that actuates the switching valve, a shift range detection unit that detects a selected shift range of the transmission, and a control unit that controls the valve actuator to actuate the switching valve in accordance with the selected transmission shift range. The switching valve has a bypass position to provide a supply of the hydraulic fluid to the lubrication-requiring portions by bypassing a transmission oil cooler. The control unit judges whether the transmission is in a low lubrication state based on a given operating parameter of the transmission and controls the valve actuator to switch the switching valve to the bypass position at the time the transmission is judged as being in the low lubrication state.

Abstract: An automatic transmission control system is provided with a disengagement malfunction determining section and a disengagement malfunction preventing section in an automatic transmission in which the frictional engaging elements are selectively engaged and disengaged to change a rotational speed of a main power source. The disengagement malfunction determining section determines a disengagement malfunction with a first frictional engaging element from among a plurality of frictional engaging elements of the automatic transmission.

Abstract: An automatic transmission control unit determines whether or not a constantly open failure, in which a switch valve cannot switch a pressure regulating valve and a second hydraulic chamber to a non-communicative state, has occurred on the basis of a parameter (an inertia phase time, for example) representing a dynamic characteristic during a shift from a first gear position to a second gear position. The determination of the constantly open failure is begun after initial variation in the parameter representing the dynamic characteristic during the shift has been eliminated through learning control in which the dynamic characteristic during the shift is caused to approach a target dynamic characteristic.

Abstract: An automatic transmission comprising a plurality of planetary gears disposed between an input shaft and an output shaft and having a plurality of rotational elements, a plurality of frictional elements selectively engaged and released for controlling rotations and connections of the plurality of rotational elements in accordance with instructions so as to realize a plurality of gear positions, rotational speed detecting means for detecting a rotational speed of a predetermined one of the plurality of rotational elements, other than the input shaft and the output shaft, and frictional element release means for releasing all of the plurality of frictional elements when it is judged that the rotational speed of the predetermined one of the plurality of rotational elements is higher than a predetermined rotational speed.

Abstract: In an automatic transmission of this invention, a determination as to whether or not a failure has occurred in a friction element is made repeatedly while a vehicle is traveling, and control to specify the failed friction element is begun when a vehicle speed falls to or below a predetermined value for the first time following detection of the failure in the friction element (S1, S3). When the failed friction element has been specified (S4, S13, S15, S24, S26, S35, S37), usable gear positions are determined on the basis of the specified friction element, whereupon shift control is performed using only the usable gear positions (S5, S14, S16, S25, S27, S36, S38, S39).

Abstract: An automatic transmission includes a planetary gear mechanism, an engagement element group including a particular engagement element having first and second pressure chambers, a pressure control valve to regulate the fluid pressure for the particular engagement element, and a selector valve arranged to connect the second pressure chamber with the pressure control valve at a first valve position, and to disconnect the second pressure chamber from the pressure control valve at a second valve position. A shift control section is configured to command a shift operation from a first gear position, to a second gear position, by controlling the selector valve to the second valve position and to supply the fluid pressure to the first pressure chamber, and to judge the selector valve to be in an abnormal state, in accordance with a parameter in the shift operation.

Abstract: In a planetary gear type stepped automatic transmission, a gear shift control to shift a gear shift stage between a first gear shift stage and a second gear shift stage is performed by a first shift control section by referring to a first gear shift control data used when the gear shift stage is switched between the first gear shift stage and the second gear shift stage, an abnormality state due to a failure of at least one of a first frictional engaging element and a second frictional engaging element is detected, and an abnormality state gear shift control is performed to shift the gear shift stage between a third gear shift stage (for example, first speed) and a fourth gear shift stage (for example, 2.5 speed) by the first shift control section, while forcefully releasing the first frictional engaging element, when detecting the abnormality state.

Abstract: A control apparatus for an automatic transmission including a plurality of frictional elements each arranged to be engaged by receiving supply of an engagement pressure regulated by a solenoid, and being arranged to attain a plurality of gear stages by combination of engagements of the frictional elements, the control apparatus includes a failure occurrence sensing section configured to sense an occurrence of a failure-induced disengagement in one of the frictional elements based on a failure of one of the solenoids, based on an engine racing by a depression of an accelerator pedal in a state in which ranges other than a parking range and a neutral range are selected during a stop of a vehicle; and a command output section configured to output a limp home mode command to attain one of the gear stages to enable the vehicle to start.

Abstract: An automatic transmission control system is provided with a disengagement malfunction determining section and a disengagement malfunction preventing section in an automatic transmission in which the frictional engaging elements are selectively engaged and disengaged to change a rotational speed of a main power source. The disengagement malfunction determining section determines a disengagement malfunction with a first frictional engaging element from among a plurality of frictional engaging elements of the automatic transmission.