A control apparatus of an automatic transmission connected to an internal combustion engine of a vehicle includes a determination unit configured to determine an operation state of a hydraulic oil temperature sensor based on comparison between a threshold and a difference between a hydraulic oil temperature of the automatic transmission and a cooling water temperature of the internal combustion engine. When the operation state of the hydraulic oil temperature sensor is determined as normal by the comparison with the threshold, the determination unit further determines the operation state of the hydraulic oil temperature sensor based on an operation state of an oil pressure sensor determined using the hydraulic oil temperature, an oil pressure of hydraulic oil, and a rotation speed.

A control apparatus of an automatic transmission connected to an internal combustion engine of a vehicle includes a determination unit configured to determine an operation state of a hydraulic oil temperature sensor based on comparison between a threshold and a difference between a hydraulic oil temperature of the automatic transmission and a cooling water temperature of the internal combustion engine. When the operation state of the hydraulic oil temperature sensor is determined as normal by the comparison with the threshold, the determination unit further determines the operation state of the hydraulic oil temperature sensor based on an operation state of an oil pressure sensor determined using the hydraulic oil temperature, an oil pressure of hydraulic oil, and a rotation speed.

An oil temperature estimation apparatus that estimates an oil temperature of a driving system of a vehicle includes a vehicle speed sensor, a saturated oil temperature acquirer, an oil temperature deviation acquirer, an oil temperature feedback value acquirer, and an estimated oil temperature acquirer. The saturated oil temperature acquirer acquires a saturated oil temperature in a running state of the vehicle at least including a vehicle speed based on the running state. The oil temperature deviation acquirer acquires an oil temperature deviation between the saturated oil temperature and an estimated oil temperature previous value. The oil temperature feedback value acquirer acquires an oil temperature feedback value based on the oil temperature deviation and the vehicle speed. The estimated oil temperature acquirer acquires an estimated oil temperature current value based on the estimated oil temperature previous value and the oil temperature feedback value.

An oil temperature estimation apparatus that estimates an oil temperature of a driving system of a vehicle includes a vehicle speed sensor, a saturated oil temperature acquirer, an oil temperature deviation acquirer, an oil temperature feedback value acquirer, and an estimated oil temperature acquirer. The saturated oil temperature acquirer acquires a saturated oil temperature in a running state of the vehicle at least including a vehicle speed based on the running state. The oil temperature deviation acquirer acquires an oil temperature deviation between the saturated oil temperature and an estimated oil temperature previous value. The oil temperature feedback value acquirer acquires an oil temperature feedback value based on the oil temperature deviation and the vehicle speed. The estimated oil temperature acquirer acquires an estimated oil temperature current value based on the estimated oil temperature previous value and the oil temperature feedback value.

A motor vehicle has an electronically controllable parking lock and an electronically controllable parking brake, which can be controlled individually or in combination. A device having an electronic control unit and a central operating element associated with the parking lock and the parking brake is provided. When the motor vehicle is at a standstill and the central operating element is actuated, the parking lock and the parking brake can be controlled in a specific type of parking-lock and/or parking-brake activation. In a first specific type, during a first actuation of the central operating element, at least the parking brake is automatically activated first. If the central operating element is then re-actuated within a predefined time window, or if the central operating element remains actuated for a predefined minimum time period, the driver is offered at least one possibility of manually selecting a specific type of parking-lock and/or parking-brake activation.

Embodiments of the present invention provide a vehicle drivetrain assembly operable in a first mode and a second mode. The vehicle drivetrain assembly comprises: a drive unit arranged to generate power to drive a vehicle (1); an automatic transmission comprising a torque converter and operatively coupled to the drive unit to receive the power; and a control system comprising one or more controllers (11), the control system being arranged to adjustably limit the maximum torque delivered to the transmission from the drive unit. When the automatic transmission is in first gear with the torque converter stalled, the control system limits the maximum torque to a first level when the vehicle drivetrain assembly is in the first mode and to a second level when the vehicle drivetrain assembly is in the second mode, the first level being lower than the second level.

Embodiments of the present invention provide a vehicle drivetrain assembly operable in a first mode and a second mode. The vehicle drivetrain assembly comprises: a drive unit arranged to generate power to drive a vehicle (1); an automatic transmission comprising a torque converter and operatively coupled to the drive unit to receive the power; and a control system comprising one or more controllers (11), the control system being arranged to adjustably limit the maximum torque delivered to the transmission from the drive unit. When the automatic transmission is in first gear with the torque converter stalled, the control system limits the maximum torque to a first level when the vehicle drivetrain assembly is in the first mode and to a second level when the vehicle drivetrain assembly is in the second mode, the first level being lower than the second level.

A method and apparatus for modifying the shift map of an automatically controlled vehicle transmission having individually selectable speed ratios. A calibrator determines launch ratio from a plurality of speed ratios and is responsive to ambient pressure and/or ambient temperature. The calibrator may be further responsive to engine speed, engine temperature, transmission temperature, gradient and direction of gradient.

A method and apparatus for modifying the shift map of an automatically controlled vehicle transmission having individually selectable speed ratios. A calibrator determines launch ratio from a plurality of speed ratios and is responsive to ambient pressure and/or ambient temperature. The calibrator may be further responsive to engine speed, engine temperature, transmission temperature, gradient and direction of gradient.

A hydraulic oil supply circuit of a work vehicle is configured to supply hydraulic oil to a transmission. A hydraulic oil warming circuit is configured to warm up the hydraulic oil. A control unit is configured to control the transmission, the hydraulic oil supply circuit, and the hydraulic oil warming circuit. The transmission includes a hydraulic clutch and a clutch control valve. The clutch control valve is configured to control the pressure of the hydraulic oil supplied to the hydraulic clutch according to a command from the control unit. When the control unit determines that the temperature of the hydraulic oil is low, it is configured to output a warming up command for operation of a warming up function. The hydraulic oil warming circuit is configured to warm up the hydraulic oil by causing a pressure loss in a flow path for the hydraulic oil.