SYSTEM DESCRIPTION
The K115 Continuously Variable Transaxle is a fully electrohydraulically controlled steel belt type continuously variable transaxle. This is a highly efficient transaxle that is controlled in conjunction with the engine, contributing to enhanced fuel efficiency and quietness without shift shock. In addition, the continuously variable transaxle has the following features:
Diagnostic function
Fail-safe function when a malfunction occurs
FUNCTION OF MAIN COMPONENTS
The main components of the K115 CVT system are as follows:
| Component | Outline | |
|---|---|---|
| Continuously Variable Transaxle Assembly | Shift Solenoid Valve SC | Used to switch control of the shift solenoid valve SLU between forward and reverse clutch control and lock-up clutch control. |
| Shift Solenoid Valve SL | ||
| Shift Solenoid Valve SLU | Performs forward and reverse clutch control or lock-up clutch control depending on the state of the shift solenoid valves SC and SL. | |
| Shift Solenoid Valve SLP | Controls the oil pressure of the primary pulley. | |
| Shift Solenoid Valve SLS | Controls the oil pressure of the secondary pulley. | |
| Transmission Revolution Sensor (NIN) | Detects the primary pulley speed. | |
| Transmission Revolution Sensor (NOUT) | Detects the secondary pulley speed. | |
| Transmission Revolution Sensor (NT) | Detects the input turbine speed. | |
| CVT Fluid Temperature Sensor | Detects the CVT fluid temperature. | |
| Oil Pressure Sensor | Detects the CVT oil pressure for belt clamping force. | |
| Stop Light Switch Assembly | Detects the state of the brake pedal. | |
| Park/Neutral Position Switch Assembly | Detects the position of the shift lever. | |
| Shift Lock Control Unit Assembly | Transmission Control Switch |
|
| Combination Meter Assembly | Shift Position Indicator | Indicates the shift lever position. |
| Malfunction Indicator Lamp (MIL) | Illuminates or blinks to alert the driver that the ECM has detected a malfunction. | |
| ECM |
|
|
| Airbag ECU Assembly | Yaw Rate Sensor | Detects the vehicle's yaw rate. |
| Acceleration Sensor | Detects the vehicle's longitudinal and lateral acceleration and deceleration. | |
| Brake Actuator Assembly | Skid Control ECU |
|
| Electric CVT Oil Pump (Oil Pump with Motor Assembly) | Keeps CVT oil pressure at an adequate level while the stop and start system is operating. | |
| Oil Pump Motor Driver | Controls the power output of the electric CVT oil pump (oil pump with motor assembly). | |
| DLC3 | Used for connecting the GTS to read diagnostic trouble codes and ECM data. | |
Tech Tips
The airbag ECU assembly incorporates the yaw rate sensor and acceleration sensor.
OIL PUMP WITH MOTOR ASSEMBLY OPERATION CONTROL
When the engine is stopped automatically by the stop and start system, the engine stop and start ECU operates the oil pump with motor assembly installed to the continuously variable transaxle to produce optimal CVT oil pressure for enhanced response of the continuously variable transaxle assembly and smooth start-off when the engine is automatically restarted.
Tech Tips
Refer to the stop and start system operation conditions.
The oil pump with motor assembly operates when the CVT oil temperature is between 25 to 100°C (77 to 212°F).
When the shift lever is in P, R or N, the engine will not be stopped by the stop and start system.
| Shift Lever Position | P | R | N | D or M |
|---|---|---|---|---|
| Brake Pedal Depressed | Does not operate | Does not operate | Does not operate | Operates |
| Brake Pedal Released | Does not operate | Does not operate | Does not operate | Operates → Does not operate* |
*: When the engine speed or vehicle speed reaches the threshold value, the oil pump with motor assembly will stop operating.