Control apparatus for automatic transmission and control method for automatic transmission

A control method for automatic transmission comprising:

• providing an operating member, a detecting sensor, a valve, and a hydraulic pressure controller, the operatinunitoperating member being used to select a range of an automatic transmission including a traveling range and a non-traveling range, the detecting sensor being configured to detect the selected range by the operating member, the valve being disposed at an oil passage that couples a hydraulic pressure supply source and a plurality of forward movement friction elements, a supply of a hydraulic pressure from the hydraulic pressure supply source to the plurality of forward movement friction elements being allowed while the traveling range is selected, the valve being configured to drive according to an operation of the operating member, the hydraulic pressure controller being disposed at the oil passage, the hydraulic pressure controller being configured to control the supplied hydraulic pressure to the plurality of forward movement friction elements;
• controlling the detecting sensor such that if the detecting sensor detects the traveling range, the hydraulic pressure controller supplies the plurality of forward movement friction elements with the hydraulic pressure;
• and
• determining, if the detecting sensor detects the traveling range and operations of all the friction elements of the plurality of forward movement friction elements are not detected, the determining determines that an operation position of the operating member is at an intermediate position between a position according to the traveling range and a position according to the non-traveling range, if the detecting sensor detects the traveling range and the operation of a part of the friction elements among the plurality of forward movement friction elements is not detected, the determining determines that the hydraulic pressure controller has a failure.

A control apparatus for automatic transmission, comprising:

• operating means for selecting a range of an automatic transmission including a traveling range and a non-traveling range;
• detecting means for detecting the selected range by the operating means;
• a valve disposed at an oil passage that couples a hydraulic pressure supply source and a plurality of forward movement friction elements, a supply of a hydraulic pressure from the hydraulic pressure supply source to the plurality of forward movement friction elements being allowed while the traveling range is selected, the valve being configured to drive according to an operation of the operating means;
• a hydraulic pressure controller disposed at the oil passage, the hydraulic pressure controller being configured to control the supplied hydraulic pressure to the plurality of forward movement friction elements;
• control means for controlling the hydraulic pressure controller to supply the plurality of forward movement friction elements with the hydraulic pressure if the detecting means detect the traveling range;
• and
• determining means for executing a determination if the detecting means detect the traveling range, the determining means being configured such that if operations of all the friction elements of the plurality of forward movement friction elements are not detected, the determining means determining that an operation position of the operating means is at an intermediate position between a position according to the traveling range and a position according to the non-traveling range, the determining means being configured such that if the operation of a part of the friction elements among the plurality of forward movement friction elements is not detected, the determining means determining that the hydraulic pressure controller has a failure.