Note:
- The CVT type is stamped on an aluminum plate attached to the engine compartment bulkhead, in the line "TRANS/AXLE".
- For the procedure for replacing the working fluid in the variator, see the chapter "Maintenance and general check and adjustment procedures".
General information
The variator consists of a continuously variable transmission (two composite pulleys and a metal belt), planetary gear (to ensure reverse movement), intermediate gear, main gear and control system elements.
The mechanical part of the variator consists of four parallel shafts (input shaft, continuously variable transmission drive pulley shaft, continuously variable transmission driven pulley shaft and final drive shaft). The input shaft is directly connected to the engine flywheel. The input shaft is connected to the drive pulley shaft via a planetary gear. The driven pulley shaft also has a starting clutch that starts the car and the drive gear of the intermediate gear. The driven gear of the intermediate gear is rigidly connected to the drive gear of the main gear.
To control the operation of the planetary gear set of the variator, a forward clutch and a reverse brake are used.
The electrical part of the variator control system consists of three parts:
- a) Sensors that determine the vehicle's condition parameters and transmit this data to the electronic control unit.
- b) The control unit, which determines the gear ratio of the continuously variable transmission, changes the direction of movement of the vehicle depending on the selected range.
- c) The actuator, which consists of electromagnetic valves.
The control unit uses electromagnetic valves to change the distance between the pulley cheeks, thus changing the gear ratio.
The pressure control solenoid valve varies the pressure (HLC) supplied to the pressure distribution control valve between the pulleys.
The electromagnetic valve for pressure distribution between pulleys (SH) distributes the pressure of the working fluid supplied to the driving and driven pulleys.
The starter clutch control solenoid valve changes the pressure supplied to the starter clutch (SC), which changes depending on the degree of opening of the throttle valve.
Manual gear ratio change mode
Some modifications have a manual mode for changing the variator gear ratio.
In this mode, there are seven fixed positions of the variator pulleys, corresponding to the gears of a conventional gearbox. The seven "gears" are changed by the driver using the upshift and downshift switches on the steering wheel. The selected gear ratio number is displayed on the instrument cluster (range from "1" to "7")
Layout of continuously variable transmission (CVT) components (sedan). 1 - engine and variator control unit, 2 - diagnostic connector, 3 - mounting block in the passenger compartment, 4 - speed sensor No.1, 5 - speed sensor No.2, 6 - electromagnetic pressure control valve, 7 - drive pulley speed sensor, 8 - electromagnetic valve for pressure distribution between pulleys, 9 - electromagnetic valve for controlling the starting clutch, 10 - electromagnetic start prohibition valve, 11 - driven pulley speed sensor, 12 - selector position sensor.
Layout of continuously variable transmission (CVT) components (hatchback). 1 - engine and variator control unit, 2 - selector lock electromagnetic valve, 3 - selector "S" position sensor, 4 - diagnostic connector, 5* - manual shift mode switch, 6 - speed sensor No.1, 7 - speed sensor No.2, 8 - pressure control electromagnetic valve, 9 - drive pulley speed sensor, 10 - pulley pressure distribution electromagnetic valve, 11 - starting clutch control electromagnetic valve, 12 - start inhibit electromagnetic valve, 13 - driven pulley speed sensor, 14 - selector position sensor, 15* - downshift switch in manual shift mode, 16* - upshift switch in manual shift mode. Note: * - models with manual switching mode.
[The article was taken from the website «www.hondabook.ru»]