AUTOMATIC TRANSMISSION SYSTEM

Clutch Pressure Optimal Control

• The ECM monitors the signals from various types of sensors, such as the transmission revolution sensor (NT) and transmission revolution sensor (NC3), allowing shift solenoid valve SL1, SL2, SL3, SL4, SL5, SLT (line pressure control solenoid assembly) and shift solenoid valve SLU (lock up control solenoid assembly) to minutely control the clutch pressure in accordance with engine output and driving conditions. As a result, smooth shift characteristics are achieved.

  

Clutch to Clutch Pressure Control

• Clutch to clutch pressure control is used for shift control. As a result, shift control in the 2nd gear or above is possible without using the 1-way clutch, and the automatic transmission has been made lightweight and compact.

• Using the fluid pressure circuit, which enables the clutches and brakes (C1, C2, C3, C4 and B1) to be controlled independently, and the high flow SL1, SL2, SL3, SL4 and SL5 shift solenoid valves, which directly control the line pressure, the ECM controls each clutch and brake accordingly with the optimum fluid pressures and timings in accordance with the information transmitted by the sensors, and then shifts the gears. As a result, highly responsive and excellent shift characteristics have been achieved.

  

Driving Response and Acceleration Management System (DRAMS)

• Driving Response and Acceleration Management System (DRAMS) is used for this vehicle. This system integrally controls the engine, transmission and other driving related controls. By integrally controlling the engine and automatic transmission using this system, quick response and a high quality driving feel in accordance with the driver's intentions are achieved, such as when accelerating or decelerating or during gear shifts.

  

1. Start Control

   
   

   • With DRAMS, engine torque will optimally be controlled in a real-time manner in accordance with speed ratios between engine speed and turbine speed so that finely controlled starting capability has been provided while balancing the "reduction of a feel of jump and suppression of tire slipping" and "smooth responsiveness" when starting.

2. Transient Shifting Control

   
   

   • Through integrated control with Electronic Throttle Control System-intelligent (ETCS-i), Electronic Spark Advance (ESA), and electronic control of the engagement and release speed of clutch and brake hydraulic pressures, excellent response and shift shock reduction have been achieved.

     

   • Engine torque control used during gear shifts has been added to the cooperative control of the engine torque control and clutch hydraulic pressure control performed during gear shifts. This enhances gear engagement characteristics during gear shifts and achieves smooth gear changes.

     

Powertrain Cooperative Control

• Integrated control of the powertrain (engine and transaxle) has created a new vehicle appeal. Powertrain cooperative control calculates the driver target motive force and target shift position in response to driver operations, the vehicle status and the road environment and performs precise control according to the engine control and ECT control conditions. As a result, driveability is improved.

• The driver target motive force is set to achieve a long pleasant acceleration when an accelerator pedal operation performed to accelerate the vehicle is detected. Also, SPORT mode is used to provide an even sportier target motive force and target gear position according to driver accelerator pedal operation, enhancing the pleasant acceleration of the turbo engine and ensuring driving appeal.

  

  Figure 1. Acceleration when Accelerator Pedal Opening Angle is Maintained at Certain Amount

  

  *1	with Control
  *2	without Control
  *3	Acceleration
  *4	Vehicle Speed

1. Linear feel improving control (Models with 2GR-FKS Engine)

   
   

   • Conventionally, drive force was dependent on the accelerator pedal operation (throttle opening) and the gear position.

   • With the linear feel improving control, optimum engine torque (throttle opening) for the gear position is achieved, reducing the frequency of downshifting.

   • Continuous drive force has been achieved by reducing the variations in drive force when downshifting, improving controllability of the vehicle during accelerator pedal operation.

     

   • By reducing changes in the acceleration rate while the vehicle speed increases, a steady linear increase in vehicle speed that does not depend on the shift range has been achieved.

     

     *1	with Control
     *2	without Control
     *3	Acceleration G
     *4	Vehicle Speed

2. Coast Downshift Control

   
   

   • The ECM performs downshift control to prevent the engine speed from decreasing, thus keeping fuel cut control operating for as long as possible. In this way, the fuel economy is improved.

   • In this control, the transmission downshifts from 8th to 7th, 7th to 6th and then 6th to 5th before fuel cut control ends when the vehicle is decelerated in the 8th gear, so that fuel cut control continues operating. In addition, the ECM performs downshifting when the vehicle is decelerated both in the 6th and 7th gears.

     Figure 2. Models with 2GR-FKS Engine

     

     Figure 3. Models with 8AR-FTS Engine

     

3. Drive Mode Select Function

   
   

   • The drive mode can be selected by operating the drive mode select or SNOW switch.

   • The selected drive mode will be shown on the multi-information display in the combination meter assembly.

   • The drive characteristics of each drive mode are as follows:

     Drive Mode	Outline
     ECO	Transmission characteristics which prioritize fuel-efficient driving are used to ensure low fuel consumption compared with that of NORMAL mode.
     NORMAL	This drive mode provides optimum driveability.
     SPORT Mode*2 SPORT S Mode*3	The ECM improves acceleration performance and responsiveness by controlling the opening of the throttle and by changing the shift point of the transmission, thus achieving a sporty drive.
     SPORT S+ Mode*3	In addition to the control when in SPORT S mode, the suspension control system, brake control system and steering control system have been integrated to shift to SPORT mode, improved operability and stability have been aimed for even without losing comfort and a control which enables operation appropriate to the driver's intention is performed.
     SNOW*1	The ECM improves starting-off performance and acceleration performance on slippery road surfaces such as snow on which the wheels may spin by controlling to restrain drive force more than when in NORMAL mode.
     CUSTOMIZE*3	The CUSTOMIZE mode allows the driver to freely set modes to his/her preferable adjustments in each of the power train control (engine/transmission), chassis control (steering/suspension), and air-conditioning control, in addition to the "ECO", "NORMAL", "SPORT S" and "SPORT S+" modes provided by default.

     *1: Except Models for G.C.C. Countries

     *2: Except F SPORT

     *3: For F SPORT

     Figure 4. Combination Switch Assembly

     

     *A	Except Models for G.C.C. Countries	-	-
     *1	Combination Switch Assembly	*2	SNOW Switch
     *3	Drive Mode Select	-	-
     *a	The illustrations shown are examples only.	-	-

     Figure 5. Optitron Meter

     

     *A	Except Models for G.C.C. Countries	-	-
     *1	Multi-Information Display	*2	SNOW Mode Indicator Light
     *3	Drive Mode Indicator Light	-	-

     Figure 6. TFT LCD Meter

     

     *A	Except Models for G.C.C. Countries	-	-
     *1	Multi-Information Display	*2	SNOW Mode Indicator Light
     *3	Drive Mode Indicator Light	-	-

4. Hill-climbing Downshift Control (Models with 8AR-FTS Engine)

   
   

   • In hill-climbing situations that require drive force, downshifting control is performed based on slope information to improve driveability. When this occurs, lock-up continues in order to achieve a direct feeling in response to accelerator operations made by the driver.

     

5. Deceleration Force Control

   
   

   • The ECM determines the gear position when the accelerator pedal is off (released completely) in accordance with the way the accelerator pedal is released (suddenly or slowly) during deceleration. In this way, unnecessary upshifts and downshifts are prevented when the accelerator pedal is off and subsequent smooth acceleration is ensured, matching the driver's intentions.

     

Multi-mode Transmission

• The driver can select the desired gear range by moving the shift lever to "+" (forward) or to "-" (backward) while the shift lever is in M. Also, the shift paddle switch (transmission shift switch assembly) can be used to change the gear range while the driver is holding the steering wheel. Thus, the driver is able to shift gears with a manual-like feel.

• When the shift lever is in D, the driver can momentarily select a desired shift range by operating the shift paddle switch (transmission shift switch assembly). Automatic shifting will be reinstated under the following conditions:

  - The vehicle has stopped.

  - The driver continues to push the shift paddle switch (transmission shift switch assembly) in the "+" direction longer than 1 second.

  - The driver depresses the accelerator pedal longer than a predetermined length of time.

• When the vehicle is being driven at a prescribed speed or higher, any attempt to shift to a lower range by operating the shift lever will not be executed, in order to protect the automatic transmission. In this case, the ECM sounds the multi buzzer in the combination meter assembly twice to alert the driver.

  

• When the shift lever is in M, the gear hold control, lock-up control, high response upshift control and blipping downshift control are used in order to improve response in accordance with the driver's operation of the accelerator pedal, shift lever or transmission shift switch, and to improve gear shift feeling.

  

1. Gear Hold Control

   
   

   • Gear shifting will not be performed under gear hold control as long as the shift lever or shift paddle switch (transmission shift switch assembly) is not operated. This makes it possible to make efficient use of highest engine speeds. However, in the following cases, operation of gear hold control is limited.

   Automatic shifting when the shift lever is in M

   When the ATF or engine coolant temperature is low, gear shifting will be performed automatically. When the ATF temperature is high, gear shifting will be performed automatically.

2. Lock-up Control

   
   

   • While the shift lever is in M, lock-up control operates from 2nd gear, transmitting the changes in engine power directly to the output shaft, the same way as with a manual transmission, and thus, direct response to the accelerator operation is achieved.

3. High Response Upshift Control

   
   

   • The high response upshift control achieves highly responsive upshift operation using the clutch to clutch pressure control, which regulates each clutch and brake quickly and precisely, and by the powertrain cooperative control, which optimally regulates engine torque during shifting.

   

4. Blipping Downshift Control

   
   

   • The blipping downshift control regulates each clutch and brake using the clutch to clutch pressure control, allowing them to be engaged smoothly and disengaged quickly. In addition, fuel injection volume is increased and engine speed is boosted by the powertrain cooperative control, thus ensuring engine brake force. In this way, a smooth and quick downshift is achieved.

   

Control to Improve Feelings of Acceleration

• Control is performed to improve the feeling of acceleration (suppress shocks) experienced when starting off or accelerating backup to speed, achieving smooth acceleration and drawing out the appeal of the vehicle.

1. Throttle Control at Launch

   
   

   • The engine output is optimally controlled with Electronic Throttle Control System intelligent (ETCS-i) in real-time in accordance with the transient force from the torque converter when the vehicle is launched. This achieves a "suppressed sense of lurching forward", "tire slippage suppression" and "improved responsiveness", ensuring excellent launch performance.

     

Lock-up Timing Control

1. Models with 2GR-FKS Engine

   
   

   • The ECM operates the lock-up timing control in order to improve the fuel economy performance.

     Lock-up Timing Control Operation

     Gear	Shift Lever Position
     	M	D, D8	D7	D6
     1st	X	X	X	X
     2nd	○*	X	X	X
     3rd	○*	X	X	X
     4th	○*	X	X	X
     5th	○*	X	X	X
     6th	○*	○	○	○
     7th	○*	○	○	-
     8th	○*	○	-	-

     Tech Tips

     ○: Operates

     X: Does not operate

     *: Direct feel improve control

     -: Not applicable

2. Models with 8AR-FTS Engine

   
   

   • The ECM operates the lock-up timing control in order to improve the fuel economy performance.

   • A torque converter with a pendulum damper is used to expand the lock-up operating range. Also, this control can be performed even when the ATF temperature is low, contributing to improved fuel economy.

     Lock-up Timing Control Operation

     Gear	Shift Lever Position or Shift Range
     	M	D, D8	D7	D6	D5	D4	D3
     1st	X	X	X	X	X	X	X
     2nd	○*	X	X	X	X	X	X
     3rd	○*	○	○	○	○	○	○
     4th	○*	○	○	○	○	○	-
     5th	○*	○	○	○	○	-	-
     6th	○*	○	○	○	-	-	-
     7th	○*	○	○	-	-	-	-
     8th	○*	○	-	-	-	-	-

     Tech Tips

     ○: Operates

     X: Does not operate

     *: Direct feel improve control

     -: Not applicable

     
   
   

   1. Downshift Lock-up Control

   
   

   1. Downshift lock-up control maintains the lock-up condition even while downshifting. As a result, a sense of unity is provided between the feeling of the engine speed increasing and the feeling of acceleration after downshifting, producing a pleasant shifting experience. Also, lock-up continues in order to restrict unnecessary fuel consumption, contributing to improved fuel economy.

      

   2. Lock-up Transition Control

   
   

   1. When lock-up is engaged, the hydraulic pressure that engages the lock-up clutch is finely controlled to reduce shocks caused by shifting, allowing for smooth engagement even from low gear ranges.

      

Flex Lock-up Clutch Control

1. Models with 2GR-FKS Engine

   
   

   • In the low-to-mid-speed range, this flex lock-up clutch control regulates the shift solenoid valve SLU (lock up control solenoid assembly) to provide an intermediate mode between the on and off operations of the lock-up clutch in order to improve the energy transmitting efficiency. As a result, the operating range of the lock-up clutch has been increased and fuel economy has been improved.

     

     

   Flex Lock-up Clutch Control Operation

   Gear	Shift Lever and Shift Range (Fixed Shift Range Mode) Position
   	D, D8	D7	D6	D5	D4
   1st	X	X	X	X	X
   2nd	X	X	X	X	X
   3rd	X	X	X	X	X
   4th	○	X	X	X	X
   5th	○*	○*	○*	○*	-
   6th	○*	○*	○*	-	-
   7th	○*	○*	-	-	-
   8th	○*	-	-	-	-

   Tech Tips

   *: Flex lock-up clutch control operates during deceleration.

   ○: Operates

   X: Does not operate

   -: Not applicable

2. Models with 8AR-FTS Engine

   
   

   • In the low-to-mid-speed range, this flex lock-up clutch control regulates the shift solenoid valve SLU to provide an intermediate mode between the on and off operations of the lock-up clutch in order to improve the energy transmitting efficiency. As a result, the operating range of the lock-up clutch has been increased and fuel economy has been improved.

     

   • For flex lock-up control, the lock-up range is expanded so that control only operates when decelerating. Also, expanding the flex lock-up range and allowing the control to operate when the ATF temperature is low contributes to enhanced fuel economy.

     Flex Lock-up Clutch Control Operation (Deceleration)

     Gear	Shift Lever Position or Shift Range
     	D, D8	D7	D6	D5	D4	D3
     1st	X	X	X	X	X	X
     2nd	X	X	X	X	X	X
     3rd	*	*	*	*	*	*
     4th	*	*	*	*	*	-
     5th	*	*	*	*	-	-
     6th	*	*	*	-	-	-
     7th	*	*	-	-	-	-
     8th	*	-	-	-	-	-

     Tech Tips

     *: Flex lock-up clutch control operates during deceleration.

     X: Does not operate

     -: Not applicable

Artificial Intelligence Shift Control (AI-shift Control)

• AI-shift control selects optimal controls in accordance with "driving environment" and the"driver's intention" based on the degree of accelerator opening, vehicle speed, brake signals, etc.

• Smooth driving and low fuel consumption have been achieved while driving normally. A strong and linear feeling of acceleration has been provided when accelerating. A direct feeling of deceleration through engine braking and high fuel efficiency have been achieved when decelerating.

  

1. Uphill/Downhill Control

   
   

   • The ECM identifies the throttle valve opening angle, accelerator pedal opening angle and vehicle speed to determine whether the vehicle is being driven uphill or downhill. Unnecessary upshift is restrained to automatically achieve optimal drive force at all times while driving uphill. Downshift is automatically conducted to achieve optimal engine brake force, while driving downhill.Additionally, on models with the 8AR-FTS engine, the exclusive control improves responsiveness of the engine, achieving the optimal driving and deceleration force for driving on uphill and downhill slopes.

     

2. Driver's Intention Support Control

   
   

   • The driver's intention support control is estimated based on the accelerator pedal operation, vehicle condition and a shift pattern that is well-suited to the driver is selected without operating the switch.

   
   

   1. Sudden Accelerator Pedal Release Control

   
   

   • When the accelerator pedal is released suddenly, the transmission is kept in gear as long as possible, which improves engine braking force.

     

   2. Sudden Accelerator Pedal Depress Control (Models with 2GR-FKS Engine)

   
   

   • When the accelerator pedal is depressed suddenly, downshifting occurs earlier providing for improved acceleration response.

     

   3. Downshifting control during hard braking

   
   

   • High engine braking force and good re-acceleration response have been achieved by actively downshifting during deceleration when hard braking is made.

     

   4. G AI-shift Control

   
   

   • When the vehicle enters a corner, this system assesses the overall vehicle condition based on signal from the G sensor signal and the driver's intention, and downshifts to the appropriate gear to obtain necessary driving force for coming out of a corner.

   • Controllability during cornering is ensured by suppressing gear shifting.