CVT SYSTEM

Automatic Shift Control (Speed Ratio Control)

1. The ECM determines the driving conditions through each input signal and selects the optimal control to achieve output which meets the driver's intentions.

   

2. 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 speed (acquired from the primary speed sensor) to match the target primary pulley speed, the ECM actuates linear solenoid valves SLP and 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.

   

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

   

4. ECO mode changes the transmission characteristics to ones which prioritize fuel efficient driving to ensure low fuel consumption compared to those of NORMAL mode. This drive mode provides optimal fuel efficiency.

Acceleration Improvement Control

1. The system determines the driver's acceleration request based on the vehicle speed and changes in the accelerator pedal position. When the system determines this request, it will change the shift characteristics to ones in which the engine speed and vehicle speed increase linearly, providing improved 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.

   

7-speed Sport Sequential Shiftmatic

1. The driver can select the desired shift range by moving the shift lever to "+" (forward) or to "-" (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. Through the engine-CVT integrated control, the pulley ratio and engine torque which correspond to various shift speeds are finely controlled, thus improving shift response and achieving reduced shifting shock.

   

3. Through cooperative control with the Electronic Spark Advance (ESA) and Electronic Throttle Control System-intelligent (ETCS-i), meticulous control of the engine torque in accordance with the transmission gear ratio and transmission shift speed realizes an improved shift response and reduction in shift shock during the upshift or downshift operation, ensuring a smooth and sharp response.

   

4. The shift position and shift range indicator is provided in 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 Range Indicator	-	-

5. 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

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

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

8. 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.

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.