Toyota Jidosha Kabushiki Kaisha

Akihide Itoh

Yuji Hattori

Kenji Matsuo

Hideaki Bunazawa

Hiroki Kondo

Mitsuhiro Fukao

Motonori Kimura

Kazuya Sakamoto

Kazuya Ishiizumi

A diagnostic apparatus for a vehicle provided with a continuously-variable transmission including a primary pulley, a secondary pulley and a belt looped over the primary and secondary pulleys, such that each of the primary and secondary pulleys includes a hydraulic actuator to which a working fluid is to be supplied. The diagnostic apparatus is configured, in event of occurrence of slippage of the belt on at least one of the primary and secondary pulleys, to infer a factor causing the slippage of the belt, based on at least one of a hydraulic pressure of the working fluid supplied to the hydraulic actuator of the primary pulley and a hydraulic pressure of the working fluid supplied to the hydraulic actuator of the secondary pulley, upon the occurrence of the slippage of the belt.

Diagnostic apparatus for vehicle

A belt-slippage diagnostic apparatus for a continuously-variable transmission that includes a primary pulley, a secondary pulley and a belt looped over the primary and secondary pulleys. The belt-slippage diagnostic apparatus includes a slippage determination portion configured to determine occurrence of slippage of the belt on at least one of the primary and secondary pulleys, when a first-order derivative of a gear ratio, which is a ratio of a rotational speed of the primary pulley to a rotational speed of the secondary pulley, is not smaller than a first threshold value and a second-order derivative of the gear ratio is not smaller than a second threshold value.

Belt-slippage diagnostic apparatus for belt-type continuously-variable transmission

A control apparatus for a power transmission system is provided. The control apparatus includes an electronic control unit. The electronic control unit is configured to, when a discharge flow rate of a mechanical oil pump is smaller than a predetermined flow rate and an electric oil pump is being driven while a vehicle is traveling, determine whether a decrease in the operating hydraulic pressure has occurred. The electronic control unit is configured to, when a first engagement device is controlled from a released state toward an engaged state, control a first control pressure such that the first control pressure in a case where a decrease in a operating hydraulic pressure has occurred is lower than the first control pressure in a case where a decrease in the operating hydraulic pressure does not occur.

Control apparatus for power transmission system

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Nagoya, Japan

Akihide Itoh