CVT SYSTEM

Automatic Shift Control (Speed Ratio Control)

1. The ECM calculates the target primary pulley speed in accordance with the accelerator pedal position signal, vehicle speed signal, and stop light switch signal, in order to attain an optimal pulley ratio and shifting speed. To adjust the actual primary pulley (acquired from the primary speed sensor) to match the target primary pulley speed, the ECM actuates linear solenoid valve SLP and linear solenoid valve SLS in order to control the pressure of primary pulley and secondary pulley. As a result, the optimal pulley ratio and shifting speed are achieved.

   

2. When the shift lever is in D, the system effects engine integrated control to optimize fuel economy characteristics and driving performance.

   

3. When the shift lever is in M, the shift characteristic is as shown below. The system will upshift automatically when the vehicle reaches the set speed during acceleration.

   

4. SPORT mode restricts the variable range of the high gear ratio to ensure a more direct feeling, and provides Deceleration Improvement Control and G AI-shift Control to support vehicle stability during cornering and to ensure responsiveness when exiting a corner by holding the optimal gear ratio. In addition, newly adopted Step Shift Control provides excellent response and linear and powerful acceleration and when driving on winding roads or situations in which gentle acceleration is required.

   Tech Tips

   
   

   • When SPORT mode is selected, the SPORT mode indicator in the multi-information display illuminates.

   • When SPORT mode is operating, SPORT mode is turned off using the steering pad switch assembly.

   • When the engine is stopped with SPORT mode on, SPORT mode is turned off.

   
   

   1. Low gear ratio shift schedule

   
   

   1. The variable range of the low gear ratio is restricted to ensure appropriate engine braking force when decelerating and to enhance engine response when accelerating.

   2. Depending on the accelerator pedal depression amount, the engine can quickly rev to and be maintained in the high speed range, ensuring quick acceleration and responsiveness.

      

   2. G AI-shift control

   
   

   1. G AI-shift control generates an appropriate engine braking force by varying the gear ratio according to the brake pedal depression force.

   2. If a certain amount of lateral G force is detected, G AI-shift control determines that the vehicle is cornering and maintains engine speed by restricting the variable gear range, ensuring excellent throttle control and appropriate driving force.

      

   3. Step Shift Control

   
   

   1. Step Upshift Control

   
   

   1. During acceleration, Step Upshift Control enables the engine speed to increase in proportion to vehicle speed and repeats upshifts to promote unconstrained and powerful acceleration.

   2. During upshift, the throttle valve is electronically controlled to improve shift response and reduce shift shock.

      

Acceleration Improvement Control

1. The system determines the driver's acceleration request based on the vehicle speed and the changes in the accelerator pedal position. When the system determines this request, it will change the shift characteristic into one in which the engine speed and vehicle speed increase linearly. This improves the acceleration feeling.

   

Deceleration Improvement Control

1. During deceleration, a pulley ratio which allows high engine speed to be maintained, is calculated, thus ensuring adequate engine braking.

2. During subsequent acceleration, the engine is controlled to generate driving force quickly.

   

Uphill/Downhill Shift Control

1. Uphill/downhill shift control helps perform optimal shifting while driving on a winding uphill or downhill road.

2. When the ECM determines the vehicle is traveling uphill, the control restricts upshifting, thus offering smooth driving.

3. If a signal indicating that the driver has operated the brake pedal is input when the ECM has determined the vehicle is traveling downhill, the control downshifts to generate optimal engine braking force.

   

4. The actual acceleration calculated from the vehicle speed signal is compared with the reference acceleration (based on level road travel) stored in the ECM to determine uphill or downhill travel.

   

   *a	Uphill	*b	Downhill
   *c	Smaller	*d	Greater
   	Reference Acceleration		Actual Acceleration

Lock-up Control

1. The lock-up operation range has been expanded from that of previous continuously variable transaxles, thus enabling control to start from low speeds.

2. The lock-up operation range during deceleration has been expanded to the low-speed range. This expands the fuel cut range and achieves excellent fuel economy.

   

   *1	Lock-up Off
   *2	Throttle Opening Angle
   *3	Lock-up On
   *4	Vehicle Speed

Flex Lock-up Control

1. In order to improve the transmission efficiency and also the fuel economy, the linear solenoid valve SLU for lock-up engagement pressure control is employed to deliver flex lock-up control that can provide more precise control than that of a conventional lock-up clutch mechanism.

2. The flex lock-up control consists of flex start control and flex lock-up control during deceleration.

3. The flex start control aggressively operates the lock-up clutch during start-off to increase the transmission efficiency, as a result, the engine can run in its most efficient operating range.

   

   

4. Flex lock-up control during deceleration is used to expand the fuel-cut range. It operates the lock-up clutch over the low vehicle speed range when the vehicle decelerates so that minimal speed difference between the engine speed and turbine speed can be maintained.

Neutral Control

1. When the vehicle speed is approximately 10 km/h (6 mph) or less during braking or the vehicle is stopped with the shift lever in D, the engine and CVT are disconnected (the forward clutch is released halfway) to reduce engine load.

   

   

7-speed Sport Sequential Shiftmatic

1. The driver can select the desired gear step by moving the shift lever to "+" (forward) or "-" (backward) while the shift lever is in M (7-speed sport sequential shiftmatic mode). Thus, the driver is able to change shift range with a manual-like feel.

2. 7-speed sport sequential shiftmatic mode can be selected from normal driving mode by moving the shift lever to M. The driver can change the gear step by selecting it using the shift lever and engine braking force is provided in accordance with the selected gear step.

   

3. The shift position and shift range indicator is provided in the multi-information display of the combination meter assembly. When the shift lever is in P, R, N or D, the shift position is indicated on the shift position and shift range indicator. When the shift lever is in M, "M" and the selected shift range is displayed on the shift position and shift range indicator.

   

   *a	When shift lever is in P, R, N or D	*b	When shift lever is in M
   *c	Shift Position Indicator	*d	Shift Range Indicator

4. In 7-speed sport sequential shiftmatic mode, the transmission automatically upshifts or downshifts under the following conditions:

   Condition	System Control
   Engine is under-revving.	1 step downshift
   Engine is over-revving.	1 step upshift

5. When the vehicle is stopped during 7-speed sport sequential shiftmatic mode, the transmission automatically downshifts to M1.

6. The ECM will restrict the selection of shift ranges if it detects a malfunction in the CVT system.

7. If the vehicle speed or engine speed exceeds or goes below a preset level in response to the driver's downshift operation request, changing the shift range will be prohibited. In this case, the buzzer in the combination meter will sound to alert the driver.