Abstract: An oil pressure supply system distributes lubrication for a dual clutch transmission and an includes a mechanical oil pump pumping oil stored in a sump while being driven by an engine; a line regulator valve directly supplying a lubrication flow rate to an input shaft and a counter shaft by controlling the oil pressure supplied from the mechanical oil pump and simultaneously supplying the lubrication flow rate to a gear train and clutch through another path; a line pressure control valve variably exhausting the lubrication oil pressure when the lubrication oil pressure supplied to the input shaft and the counter shaft is a predetermined value or more; an electric oil pump pumping the oil depending on a control of a transmission control unit; a first lubrication switch valve selectively blocking oil pressure supplied from the electric oil pump to the gear train and the clutch; and a second lubrication switch valve switching a flow path so that oil pressure supplied from the line regulator valve and the first l

Abstract: Provided is a hydraulic pressure control device. A hydraulic pressure control device supplies hydraulic pressure to a piston using solenoid valves and performs 2:1 switching processing of stopping the supply of hydraulic pressure to the piston using a solenoid valve when the piston is switched to a parking locked state. When the piston is not switched to a side that is to be a parking locked state, hydraulic pressure is supplied to two solenoid valves, and 2:0 switching processing of stopping the supply of hydraulic pressure to the piston by solenoid valves is performed. Then, a reporting processing of reporting that at least one of the solenoid valves has failed is performed.

Abstract: The present disclosure provides an oil pressure supply system of an automatic transmission for a vehicle. The system may include: a mechanical oil pump; a line regulator valve configured to stably control the oil pressure supplied through the line pressure path and to supply the oil pressure to a first path; a torque converter control valve configured to control the oil pressure supplied through the first path and to supply the oil pressure to a second path and a third path; a torque converter lockup clutch control valve; an electric oil pump; a switch valve disposed on the seventh path and configured to open and close the oil pressure supplied to an eighth path; and a flow control valve configured to control a portion of the oil pressure supplied to the eighth path and to supply the portion of the oil pressure to the cooling/lubricating unit through a ninth path.

Abstract: A control apparatus includes a select lever, an inhibitor switch, a manual valve, a first SOL, a second SOL, and a controller. The controller controls the first SOL and the second SOL such that a hydraulic pressure is supplied to a first friction element and a second friction element when the inhibitor switch detects a D range. The controller determines that an operation position is at an intermediate position when operations of the first friction element and the second friction element are not detected. The controller determines that the first SOL has a failure when the operation of the first friction element is not detected.

Abstract: A method of controlling a vehicle active suspension system may include, in response to an object being detected forward of the vehicle and a vehicle speed exceeding a threshold, identifying an object classification associated with the object. The method may further include actuating the active suspension system to induce a vibration signature in the vehicle based on the object classification such that a different identified object classification corresponds to a different vibration signature.

Abstract: A range switching device for switching supply and non-supply of a source pressure based on a hydraulic pressure from a hydraulic pressure generating source to a parking device, the parking device being switched into a parking release state while the source pressure is supplied thereto and being switched into a parking state while the source pressure is not supplied thereto.

Abstract: A vehicle active suspension system, a vehicle, and a method of controlling a vehicle active suspension system are provided. The vehicle active suspension system may include a suspension actuator and a controller. The controller may be programmed to, in response to an object being detected within a predetermined range of a vehicle while a vehicle speed is greater than a threshold speed, categorize the object into at least one of a plurality of predefined categories. The controller may be further programmed to actuate the suspension actuator according to a predefined actuation profile.

Abstract: A variety of methods and arrangements for determining conditions when an engine-decoupling friction interface may be locked-up during skip-fire operation of an internal combustion engine are described. In some embodiments, the engine-decoupling friction interface is the lockup clutch of a torque converter situated in a powertrain that transmits motive power from the engine to a wheel. Rotation of the wheel causes vehicle motion.

Abstract: Calibration of an engine disconnect clutch for a hybrid electric powertrain. The clutch is prestroked while an engine and machine are stopped. A machine torque is increased until the machine starts rotating. A pressure of the clutch is adjusted as a function of a torque produced by the machine when the machine started rotating.

Abstract: A hydraulic pressure supply system may generate low hydraulic pressure and high hydraulic pressure using oil stored in an oil pan and may supply the low hydraulic pressure and the high hydraulic pressure respectively to a low pressure portion and a high pressure portion in which the hydraulic pressure supply system may include: a low-pressure hydraulic pump; a first switch valve; a low-pressure regulator valve controlling the hydraulic pressure supplied from the first switch valve and supplying the hydraulic pressure to the low pressure portion; a high-pressure hydraulic pump discharging the raised hydraulic pressure to a high-pressure line; a second switch valve disposed between the first low-pressure line and the high-pressure line, a high-pressure regulator valve controlling the hydraulic pressure supplied from the high-pressure hydraulic pump and supplying the stable high hydraulic pressure to the high pressure portion; a bypass line bypassing the first switch valve.

Abstract: A hydraulic control system of a continuously variable transmission for a vehicle reduces cost and improves quality reliability by adding switch valve function to a manual valve. The hydraulic control system may control a first brake operated at a first forward speed, a first clutch operated at a second forward speed, and a second brake operated at a reverse speed. The first clutch and the second brake may be operated by operation pressure controlled by a first proportional control solenoid valve and supplied through a manual valve, and the first brake may be operated by operation pressure controlled by a second proportional control solenoid valve, wherein the second proportional control solenoid valve controls hydraulic pressure received from the manual valve to be supplied to the first brake as the operation pressure.

Abstract: A hydraulic control system for a transmission includes a source of pressurized hydraulic fluid, a manual valve, and a default valve. A first set of solenoids are configured to selectively engage at least one of a plurality of shift actuators. The first set of solenoids is open when de-energized. A second set of solenoids is configured to selectively engage at least one of the plurality of actuators. The second set of solenoids is closed when de-energized. A low speed default gear is engaged when the first and second sets of solenoids are de-energized and the transmission is operating in a low speed gear ratio. A high speed default gear ratio is engaged when the first and second sets of solenoids are de-energized and the transmission is operating in a high speed gear ratio.

Abstract: Features for varying speeds available and/or range of operation of transmissions are provided for use in high performance, increased efficiency, and/or other applications. Increased performance and/or efficiency may be obtained by using additional speeds or gear ranges to maintain drivetrain operation within maximum power and/or efficiency bands of internal combustion engine operation.

Abstract: In a transmission control device with a control unit, to eliminate a tooth-on-tooth position in a transmission shifting unit, a transmission clutch is adjusted to a nominal clutch value. In at least one operating mode, the control unit is designed to specify a prescribed clutch value, which is independent of any intermediate clutch value setting.

Abstract: A hydraulic circuit for supplying hydraulic pressure to frictional engagement elements in an automatic transmission including an oil passage connecting an output port through which a drive pressure is output, and a second signal pressure port, of a second clutch application relay valve, and an oil passage connecting an output port through which a modulator pressure is output and the second signal pressure port, are formed in a valve body and arranged such that it is possible to open the oil passage, as well as close the oil passage, with an oil passage closing member. With the hydraulic circuit it is possible to change a formed speed in response to a shift operation when a shift, after being operated from a travel position to a non-travel position, is returned again from the non-travel position, at a time of failure.

Abstract: A hydraulic control apparatus of an automatic transmission which can supply a hydraulic oil pressure to one or more hydraulic servos of frictional engagement elements at a failure time when a de-energized condition is attained. The apparatus includes a normally closed type first solenoid valve for generating the hydraulic oil pressure, and a normally open type second solenoid valve for outputting a first signal pressure for adjusting and controlling an oil pressure to a line pressure; a signal output device for outputting the line pressure or a modulator pressure.

Abstract: A power transmission device that includes a clutch that transmits power from a motor to an axle; a first pump that is driven by power from the motor to generate and output fluid pressure; a second pump that receives and is driven by a supply of electric power to generate and output fluid pressure; a line pressure generating valve that is operated by operation fluid input to an operation input port, and regulates fluid pressure output from the first pump to generate a line pressure for engaging the clutch; and a switching valve that switches between a first connection state and a second connection state.

Abstract: A control device controlling a vehicle's automatic transmission. The automatic transmission engages first and second friction engagement elements by fluid pressure from a pump operating using motive power from the vehicle's motor when a shift position is at a reverse traveling position, places the first friction engagement element on standby at a predetermined pressure that is higher than a stroke starting pressure by which a piston stroke is started and lower than a complete engagement pressure or engages the first friction engagement at the complete engagement pressure when the shift position is at a non-traveling position, and engages a third friction engagement element as a starting shift speed when the shift position is at a forward traveling position.

Abstract: In a control of a vehicular automatic transmission, an engaging device provided in a power transmission path between an engine and driving wheels is brought into a slipping state or a release state when a certain neutral control condition is satisfied while a shift lever is placed in a running position, the engaging device is engaged so as to increase a torque transmission capacity thereof when a certain neutral control cancellation condition is satisfied during neutral control under which the engaging device is in the slipping state or the release state, and an engaging pressure of the engaging device is held at a constant pressure level for a given period of time when an accelerator pedal is depressed while the engaging device is engaged so as to increase the torque transmission capacity thereof.

Abstract: A shift by wire control for a multi-speed vehicle transmission is provided. The control includes a shift by wire shift valve in fluid communication with other shift valves and clutch trim valves to provide double blocking features in the neutral range and a reverse range. The shift by wire valve is configured with multiple differential areas to provide failure modes for all forward ranges.

Abstract: A shift control method of an automatic transmission controls a skip shift from a first shift-speed achieved by engagements of first and second frictional elements to a second shift-speed achieved by engagements of third and fourth frictional elements, wherein the engagements of the third and fourth frictional elements is controlled after completion of releases of the first and second frictional elements.

Abstract: A power transmission device that includes a clutch that transmits power from a motor to an axle; a first pump that is driven by power from the motor to generate and output fluid pressure; a second pump that receives and is driven by a supply of electric power to generate and output fluid pressure; a pressure regulating valve that regulates a pressure of operation fluid output from the first pump, and delivers at least a portion of operation fluid discharged in connection with the pressure regulation to a lubrication target for use as lubricant; and a switching valve that switches between a first connection state and a second connection state.

Abstract: A hydraulic control device for a multi-speed automatic transmission includes friction engagement elements, several hydraulic servos that engage and release the friction engagement elements, solenoid valves for engagement control, and a sorting switch valve that allocates engagement pressure from at least one of the solenoid valves for engagement control to two of the hydraulic servos. The sorting switch is switched between a first position that supplies engagement pressure to one of the two hydraulic servos in at least a Reverse, non-drive range and a specific Forward gear range, and a second position that supplies engagement pressure to the two hydraulic servos in other than the Forward range.

Abstract: The present invention provides a control system for a dual clutch automatic transmission having a torque converter. The transmission provides seven forward speeds or gear ratios and reverse. The control system includes a hydraulic pump, a pressure regulator assembly and control valves that provide and release pressurized hydraulic fluid to the torque converter, a pair of input clutches and eight synchronizer clutches. A first pair of control valves are high flow rate valves which are capable of rapidly engaging and disengaging the input clutches. A second pair of high flow rate valves, control valves and spool valves provide a branching control circuit which controls engagement and disengagement of the synchronizer clutches. A control valve linked to the shift lever blocks hydraulic fluid flow to the first pair of high flow rate valves to inhibit input clutch activation when the shift lever is in Park or Neutral.

Abstract: A transmission device has at least two change-under-load shift elements with transmission capacities that are varied an actuation device. A method for operating a drive train including transmission and drive engine includes a step that when the transmission is shifted, one of the shift elements, which is engaged in the force flow, is disengaged by the actuation device and the other shift element, which is engaged, is disengaged. The actuation device includes an actuator which applies an actuating force to actuate the shift elements and a coupling device by which the actuator communicates with the shift elements to actuate them, such that an actuating force of the actuator, which is actuating the shift element to be disengaged, can be reduced, while an actuating force of the actuator, which is actuating the shift element to be engaged can simultaneously be increased.

Abstract: A engine control system for an automatic transmission includes an engine torque control module that increases engine torque from a first torque level to a second torque level during a period before a shift from a first gear ratio to a second gear ratio, wherein the first gear ratio is greater than the second gear ratio, wherein the first torque level is based on driver input and vehicle speed, and wherein the second torque level is based on the first torque level and the first and second gear ratios. A transmission control module decreases a torque capacity of a first clutch to a third torque level during the period and increases a torque capacity of a second clutch to a fourth torque level during the period, wherein the fourth torque level is based on the second torque level and a torque gain of the second clutch.

Abstract: A dual clutch transmission comprises a first clutch to be engaged for setting any one of forward-traveling odd-numbered speeds and a second clutch to be engaged for setting any one of forward-traveling even-numbered speeds. The dual clutch transmission establishes a desired forward-traveling speed by alternately engaging/disengaging the first and second clutches. A backward-traveling drive train is adapted to be driven by engaging one of the first and second clutches. When a reverse mode is established by a mode setting means, the one of the first and second clutches is engaged to drive the backward-traveling drive train by setting a speed change manipulator at a backward-traveling position, and the other of the first and second clutches is engaged to drive a fixed one forward-traveling speed drive train by setting the speed change manipulator at a forward-traveling position.

Abstract: A method for operating an automatic transmission of a motor vehicle, in particular a variable-speed transmission. The automatic transmission includes at least five shift elements and to transfer torque or force transfer in a forward gear and a reverse gear at least three shift of the at least five elements are engaged. When shifting the automatic transmission from a neutral position to a forward or a reverse gear, at least one of the three shift elements of the automatic transmission that are engaged in the respective forward or reverse gear, is engaged in a controlled manner.

Abstract: A hydraulic control apparatus for an automatic transmission includes a forward travel engaging element, a reverse travel engaging element, a first signal electromagnetic valve, a first switching valve, and a second switching valve. The hydraulic control apparatus is structured so as to change the output state of the signal pressure of the first signal electromagnetic valve when changing from the reverse travel shift position and/or shift range to the non-travel shift position and/or shift range and when changing from the forward travel shift position and/or shift range to the non-travel shift position and/or shift range, and to enable quick draining of hydraulic pressure of the hydraulic servo of the reverse travel engaging element and hydraulic pressure of the hydraulic servo of the forward travel engaging element.

Abstract: A shift control apparatus for an automatic transmission includes a pre-shift device that operates a predetermined synchromesh, based on a prediction by a predicting device. It thereby couples together a transmission input shaft (with a friction transfer mechanism that has not been used to effect a current gear position) and a transmission output shaft, through a predetermined gear train, and brings them into a standby state. The time when it is determined that the friction transfer mechanism that has not been used to effect of the current gear position has been disengaged is taken as the timing with which the synchromesh coupling operation by the standby control is started, regardless of the completion of the achievement of the current gear position.

Abstract: Described is a method for controlling a transmission for motor vehicles, especially an automatic transmission or an automatic gearbox, where a gear ratio (“1”, “2”, “3”, “4”, “5”, “6”) is adjusted according to operating conditions by means of pre-determined shifting programs (“0”, “Eco”, “Normal”, “Sport”, “Mountain II”, “Warm-up”, “Tip”) and corresponding specific shifting values (HS45, RS43) and where in relation to a vehicle's actual operating condition at least one special function (“Curve Recognition KE”, “Rapid Drive Pedal Release FO”, “Spontaneous Delay Vehicle SVF”, “Drive Speed Control FGR”, “Drive Dynamic control ESP”) is activated, which prevents the change from an actual gear ratio to a target gear ratio requested by a shifting program within a pre-determined operating range of a vehicle. In a first version of the method, the operating range, wherein a gear ratio change of the transmission is prevented, is changed in relation to applied specific values that depend on the operating condition.

Abstract: A gearbox arrangement for a drive train of a motor vehicle, such as a double clutch gearbox arrangement or a power shift gearbox arrangement, has at least one group of gear-shifting elements (1, 2) which can be actuated for engaging and disengaging at least one respective gear of the gearbox arrangement in that they are moved relative to a gearbox housing between at least one neutral position, in which no gear associated with the gear-shifting element is engaged, and at least one engaged-gear position, in which a gear associated with the gear-shifting element and the engaged-gear position is engaged.

Abstract: The present invention comprehends a plurality of embodiments of a hydraulic control system for various configurations of dual clutch transmissions. The hydraulic control systems all include a regulated source of pressurized hydraulic fluid including an electric pump, a filter and an accumulator, a pair of pressure control valves and a branching hydraulic circuit including pressure or flow control valves, spool or logic valves and two position valves which collectively supply and exhaust hydraulic fluid from a plurality of shift actuators. The actuators are connected to shift rails which include shift forks and are slidable to engage synchronizers and positive clutches associated with the various gear ratios.

Abstract: A shift control method of an automatic transmission according to an exemplary embodiment of the present invention may control a shift from an N speed achieved by engagement of first and second frictional elements to an N-3 speed achieved by engagement of third and fourth frictional elements, wherein release of the second frictional element is completed after release of the first frictional element begins, and engagement of the fourth frictional element begins after engagement of the third frictional element begins, wherein the engagement of the third frictional element is completed after the release of the second frictional element is completed.

Abstract: A dual purpose pressure adjusting valve provides a hydraulic pressure upon failure of electric power supply and controls the hydraulic pressure selectively directed toward a high clutch and a low & reverse brake using a line pressure, that bypasses a manual valve, as a source pressure. A switching valve switches hydraulic pressure feeding passages of the high clutch and low & reverse brake in response to selection of a range position between D-range position and R-range position. A first rotation member and a transmission input shaft are connected to each other when the high clutch is engaged. The first rotation member is a member other than a transmission output gear. A high clutch inhibitor valve uses D-range pressure PD as a signal pressure and is arranged between the switching valve and the high clutch.

Abstract: A control apparatus of an automatic transmission having first and second frictional engagement elements that achieve lower and higher speed gear stages respectively, includes a target value determination section setting a rotation speed difference between input and output sides of the frictional engagement element, a total torque capacity calculation section calculating a total torque capacity, a distribution ratio determination section setting a distribution ratio of the total torque capacity to the first and second frictional engagement elements, an individual torque capacity calculation section calculating individual torque capacities respectively required of the first and second frictional engagement elements, and an engagement control section controlling engagement conditions of the first and second frictional engagement elements in accordance with the individual torque capacity.

Abstract: An electro-hydraulic control system is provided for a transmission, which is preferably a countershaft transmission, that has a three-position dog clutch actuator valve to control the position of a three-position dog clutch. At least one of the positions of the dog clutch actuator valve is established by pressurized fluid directed to the dog clutch actuator valve by two logic valves, both of which are controlled to direct pressurized fluid elsewhere in the hydraulic control system, as well.

Abstract: A transmission apparatus including an automatic transmission that is mounted in a vehicle and is capable of engaging a first engagement element and a second engagement element among a plurality of engagement elements when shift-operated to a reverse position, and engaging the first engagement element when shift-operated to a neutral position.

Abstract: A method of controlling a vehicle transmission during a gear change thereof, the method comprising operating a plurality of power shift clutches to disengage the power shift input gearing and the power shift output gearing, disengaging the driving connection between the range shift input shaft and the range shift output shaft by means of the range selection gearing, engaging at least two of the power shift clutches to vary the rotational speed of the power shift output shaft and hence the range shift input shaft, and operating the range selection gearing to establish a driving connection between the range shift input shaft and the range shift output shaft.

Abstract: The present invention provides a control system for a dual clutch automatic transmission having a torque converter. The transmission provides seven forward speeds or gear ratios and reverse. The control system includes a hydraulic pump, a pressure regulator assembly and control valves that provide and release pressurized hydraulic fluid to the torque converter, a pair of input clutches and eight synchronizer clutches. A first pair of control valves are high flow rate valves which are capable of rapidly engaging and disengaging the input clutches. A second pair of high flow rate valves, control valves and spool valves provide a branching control circuit which controls engagement and disengagement of the synchronizer clutches. A control valve linked to the shift lever blocks hydraulic fluid flow to the first pair of high flow rate valves to inhibit input clutch activation when the shift lever is in Park or Neutral.

Abstract: A shift shock reducing apparatus for a power train having an engine and an automatic transmission having a frictional element that is to be engaged at upshift, comprising a control section that executes, during upshift, a torque down of the engine that starts before the start of an inertia phase in which a gear ratio of the transmission is changing from a before-shift gear ratio to an after-shift gear ratio, and a control section that makes larger a rising gradient of working oil pressure that is supplied to the frictional element to be engaged at upshift when the torque down that starts before the start of the inertia phase is executed than that when the torque down is not executed.

Abstract: A hydraulic control apparatus for an automatic transmission includes a first solenoid valve, a second solenoid valve, a third solenoid valve, a preliminary shift speed switch valve, and an oil pressure supply switch valve, which is switched between a normal-state position where the first, second, and third working fluid pressures can be supplied to the hydraulic servos of the first, second, and third friction engagement elements, respectively, and a failure-state position where the first and second preliminary oil pressures can be supplied to the hydraulic servos of the first and second friction engagement elements, respectively, and a line pressure can be supplied to the hydraulic servo of the third friction engagement element, during a failure that causes de-energization.

Abstract: An automatic transmission includes six forward speeds and a reverse speed and includes first and second clutches, first, second, and third brakes, and first, second, and third planetary gear sets. An oil pressure control system of the transmission includes a first clutch and second brake controller allowing the first clutch to receive a fastening pressure in fourth, fifth, and sixth speeds, allowing the second brake to receive a fastening pressure in first speed and reverse, and allowing an operation state of the first clutch to be sustained upon operation of the first clutch; a second clutch controller allowing the second clutch to receive a fastening pressure in third and fifth speeds and reverse; a first brake controller allowing the first brake to receive a fastening pressure in second and sixth speeds; and a third brake controller allowing the third brake to receive a fastening pressure in first through fourth speeds.

Abstract: A converterless, multiple-ratio transmission and ratio shift control method wherein smoothness of power-on upshifts and downshifts and power-off upshifts and downshifts is achieved by closed loop control of slip speed and friction element actuating pressure for an oncoming friction element, the data used during the closed loop control including speed sensor information for multiple friction elements during upshift and downshift events.

Abstract: In a shift control device and a shift control method for an automatic transmission, when the shift range is switched from a non-travel range to a travel range, a squat control of temporarily forming a high-speed step that is smaller in speed change ratio than the first speed change step by engaging a first engagement element and a second engagement element, and then forming the first speed change step by releasing the second engagement element. In the case of standing-start of the vehicle in the high-speed step, the squat control is ended before the first speed change step is formed by releasing the second engagement element.

Abstract: Method of operating a drivetrain, comprising at least an automatic transmission and a drive motor, for improving a speed of successive upshifts or successive downshifts in an overlap manner so that, during a first upshift or downshift, at least one shift element, required for a subsequent second upshift or downshift, is prepared during the first upshift or downshift and, when a synchronization point is reached, the subsequent second upshift or downshift can be carried out immediately. Two successive respective upshifts or downshifts can be carried out as an overlapping single shift by actuating first, second and third shift elements. Implementing the first and the second upshifts or downshifts so that actuation of the second shift element, from the first upshift or downshift to the subsequent second upshift or downshift, occurs via a minimum selection of a first alternative or by a maximum selection of a second alternative.

Abstract: A hydraulic control system for an automatic transmission, which includes a brake, used to establish a first gear step and a reverse gear step. The hydraulic control system includes a first solenoid valve, a second solenoid valve and a control valve, which is switched by a hydraulic signal from the second solenoid valve, and that are operated simultaneously to engage the first-gear step and reverse gear step engagement element; and an neutral gear position engagement control unit that activates both solenoid valves when a shift lever is shifted to neutral to engage the brake. Thus, the generation of a shock may be prevented when the shift lever is shifted from the N position to an R position.

Abstract: A system for controlling a shifting during shifting, in which a frictional element is re-engaged in mid-course of being released, includes: one or more detectors for detecting driving information of a vehicle and generating one or more signals corresponding thereto; a transmission control unit for receiving the signals from the detectors and generating a control signal; and an actuator for receiving the control signal and generating a control pressure for controlling a transmission. The transmission control unit performs a control method of the shifting during shifting. The method includes: detecting driving information of a vehicle; determining whether the shifting during shifting is occurring; if the shifting during shifting is occurring, maintaining a control pressure at a stand-by pressure; determining whether an engaging condition of the frictional element is satisfied; and increasing the control pressure of the frictional element.

Abstract: The present invention provides advanced hardware diagnostic detection for the clutch control components in a hydraulic control module of a multi-mode hybrid transmission. The detection scheme of the present invention utilizes pressure switch sensors to detect the position of each of the valves associated with the clutch control mechanization. The mechanization of these sensors with the valves provides the ability to clearly define the position of each of the valves, while also enabling the transmission electro-hydraulic control module (TEHCM) to diagnose the state of health of each pressure switch. This will allow the diagnostics to differentiate between a failed switch and a failed (e.g., “stuck” or “out of position”) valve. The present invention offers the ability to safely diagnose the clutch control components in a power transmission, while preventing unexpected and undesired shift sequencing within the transmission.

Abstract: An activation control device for clutch packs of a hydraulic double clutch is described and illustrated, and in some embodiments comprises a first pressure line having a filling valve and leading from an oil pressure source to the first clutch pack; a second pressure line having a filling valve and leading from the oil pressure source to the second clutch pack; and first and second draining valves coupled to the first and second pressure lines, respectively, the first draining valve located between the filling valve of the first pressure line and the first clutch pack, and the second draining valve located between the filling valve of the second pressure line and the second clutch pack.