Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

A control device provided in a gear shifting device includes an electronic control unit. The electronic control unit determines whether an abnormality of the gear shifting device has occurred, performs a fail-safe process of switching the frictional engagement element corresponding to an abnormality to a disengaged state and fixing the gear shift ratio of the gear shifting device when it is determined that an abnormality has occurred, determines whether the abnormality has been relieved based on a behavior of an input signal at the time of operating a drive device of the frictional engagement element corresponding to an abnormality on condition that the frictional engagement element is maintained in the disengaged state after it is determined that the abnormality has occurred, and releases the fail-safe process when it is determined that the abnormality has been relieved.

A control device provided in a gear shifting device includes an electronic control unit. The electronic control unit determines whether an abnormality of the gear shifting device has occurred, performs a fail-safe process of switching the frictional engagement element corresponding to an abnormality to a disengaged state and fixing the gear shift ratio of the gear shifting device when it is determined that an abnormality has occurred, determines whether the abnormality has been relieved based on a behavior of an input signal at the time of operating a drive device of the frictional engagement element corresponding to an abnormality on condition that the frictional engagement element is maintained in the disengaged state after it is determined that the abnormality has occurred, and releases the fail-safe process when it is determined that the abnormality has been relieved.

Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

A method for operating a pneumatic actuating system of a transmission. The actuating system has an air reservoir at a first pressure. The reservoir couples an actuating space of the actuating system which is at a second pressure, and the actuating space couples, via control valves, shifting cylinders. When conducting a transmission gearshift, an air mass delivered to the active shifting cylinders via corresponding control valves, and an air mass sum including a nominal air mass in the active cylinders required for accomplishing the gearshift and an actual basic leakage from the activated shifting cylinder are determined. A defect leak in the pneumatic actuating system is recognized, if the air mass delivered to the active shifting cylinders is larger than the air mass sum. If a defect leak is recognized, the control valves coupling the actuating space and the shifting cylinders are shut off for a period of time.

A method for operating a pneumatic actuating system of a transmission. The actuating system has an air reservoir at a first pressure. The reservoir couples an actuating space of the actuating system which is at a second pressure, and the actuating space couples, via control valves, shifting cylinders. When conducting a transmission gearshift, an air mass delivered to the active shifting cylinders via corresponding control valves, and an air mass sum including a nominal air mass in the active cylinders required for accomplishing the gearshift and an actual basic leakage from the activated shifting cylinder are determined. A defect leak in the pneumatic actuating system is recognized, if the air mass delivered to the active shifting cylinders is larger than the air mass sum. If a defect leak is recognized, the control valves coupling the actuating space and the shifting cylinders are shut off for a period of time.