A controller drives a shifting actuator to move a first engagement member from an original position of a first engagement portion in one direction along a relative motion path and acquires first position information representing a first position, the first position being a position where the first engagement portion moved in the one direction contacts a second engagement portion. The controller drives the shifting actuator to move the first engagement member from the original position in the other direction along the relative motion path and acquires second position information representing a second position where the first engagement portion moved in the other direction contacts the second engagement portion. The controller calculates a center position of the first engagement portion on the relative motion path from the acquired first position information and the acquired second position information, compares the calculated center position to the original position.

A controller drives a shifting actuator to move a first engagement member from an original position of a first engagement portion in one direction along a relative motion path and acquires first position information representing a first position, the first position being a position where the first engagement portion moved in the one direction contacts a second engagement portion. The controller drives the shifting actuator to move the first engagement member from the original position in the other direction along the relative motion path and acquires second position information representing a second position where the first engagement portion moved in the other direction contacts the second engagement portion. The controller calculates a center position of the first engagement portion on the relative motion path from the acquired first position information and the acquired second position information, compares the calculated center position to the original position.

The transmission control unit includes a gear ratio abnormality determination unit and a limp home control unit. The gear ratio abnormality determination unit is configured to determine that a gear ratio is abnormal when, during travelling at a predetermined gear position, a difference between an actual gear ratio, which is calculated based on a transmission input shaft rotation speed and a transmission output shaft rotation speed, and a set gear ratio at the predetermined gear position is equal to or greater than a set value. The limp home control unit is configured to, when the gear ratio abnormality determination unit determines that the gear ratio is abnormal, output a disengagement instruction for disengaging all of the plurality of friction elements, when it is confirmed that a neutral state is shifted to according to the output of the disengagement instruction, determine engagement/disengagement of a specific friction element among the plurality of friction elements based on rotation/stop information of a rotation member of the stepped transmission mechanism, and determine an evacuation gear position based on determination information on the engagement/disengagement of the specific friction element, and shift the gear position to the determined evacuation gear position.

The transmission control unit includes a gear ratio abnormality determination unit and a limp home control unit. The gear ratio abnormality determination unit is configured to determine that a gear ratio is abnormal when, during travelling at a predetermined gear position, a difference between an actual gear ratio, which is calculated based on a transmission input shaft rotation speed and a transmission output shaft rotation speed, and a set gear ratio at the predetermined gear position is equal to or greater than a set value. The limp home control unit is configured to, when the gear ratio abnormality determination unit determines that the gear ratio is abnormal, output a disengagement instruction for disengaging all of the plurality of friction elements, when it is confirmed that a neutral state is shifted to according to the output of the disengagement instruction, determine engagement/disengagement of a specific friction element among the plurality of friction elements based on rotation/stop information of a rotation member of the stepped transmission mechanism, and determine an evacuation gear position based on determination information on the engagement/disengagement of the specific friction element, and shift the gear position to the determined evacuation gear position.

A shift device includes a shift switching member including a plurality of valley portions corresponding to shift positions, a motor including a rotor and a stator and configured to drive the shift switching member, a first drive system including a first inverter configured to output a voltage for driving the motor, a second drive system provided separately from the first drive system and including a second inverter configured to output a voltage for driving the motor; and a positioning member configured to be fitted into any one of the plurality of valley portions of the shift switching member to establish the corresponding shift position. When driving the motor, the shift position is switched by the voltages output from the first drive system and the second drive system.

A motor sticking diagnosis and repair method includes the steps of, when an operation of a shift lever is detected, determining whether a current position matches a target position, when the current position does not match the target position, rotating the motor toward the target position, determining once again whether the current position matches the target position after rotation of the motor, when the current position does not match the target position, diagnosing whether the motor sticking has occurred, when the motor is diagnosed as being stuck, allowing the motor to switch to a free-rotation mode by temporarily blocking the current being applied to the motor upon sticking diagnosis, and selecting either a first repair strategy or a second repair strategy depending on whether the position of the motor changes after switching to the free-rotation mode.

A motor sticking diagnosis and repair method includes the steps of, when an operation of a shift lever is detected, determining whether a current position matches a target position, when the current position does not match the target position, rotating the motor toward the target position, determining once again whether the current position matches the target position after rotation of the motor, when the current position does not match the target position, diagnosing whether the motor sticking has occurred, when the motor is diagnosed as being stuck, allowing the motor to switch to a free-rotation mode by temporarily blocking the current being applied to the motor upon sticking diagnosis, and selecting either a first repair strategy or a second repair strategy depending on whether the position of the motor changes after switching to the free-rotation mode.

The invention relates to a method for operating an on-board electrical network (4) of a motor vehicle (2), having a first voltage circuit (I) and a second voltage circuit (II), the first voltage circuit (I) having a first operating voltage which is higher than a second operating voltage in the second voltage circuit (II), wherein the first voltage circuit (I) is connected to the second voltage circuit (II), the first voltage circuit (I) having a battery (10) and the second voltage circuit (II) having at least one main battery (12a) and a second main battery (12b), wherein the first main battery (12a) and the second main battery (12b) have essentially the same capacity, and wherein components of the motor vehicle (2) are supplied with electrical operating energy from the first main battery (12a) and/or the second main battery (12b) by means of a switch assembly (14).

A clutch includes a clutch disk that rotates by receiving motive power from an engine and a clutch plate switched between an engaged state in which it is engaged with the clutch disk and a disengaged state in which it is not engaged with the clutch disk. A controller calculates a coefficient of friction μ between the clutch disk and the clutch plate based on a time period Δt elapsed from a first time point when the number of relative rotations of the clutch disk and the clutch plate attains to a first number of rotations to a second time point when a second number of rotations smaller than the first number of rotations is attained, in a state in which the clutch disk rotates while transfer of motive power from the engine to the clutch disk is cut off and in the engaged state.

A clutch includes a clutch disk that rotates by receiving motive power from an engine and a clutch plate switched between an engaged state in which it is engaged with the clutch disk and a disengaged state in which it is not engaged with the clutch disk. A controller calculates a coefficient of friction μ between the clutch disk and the clutch plate based on a time period Δt elapsed from a first time point when the number of relative rotations of the clutch disk and the clutch plate attains to a first number of rotations to a second time point when a second number of rotations smaller than the first number of rotations is attained, in a state in which the clutch disk rotates while transfer of motive power from the engine to the clutch disk is cut off and in the engaged state.