Automatic transmission device (automatic transmission) Toyota Corolla 120 body
Hydraulic transformer
* Converts engine torque and ensures smooth gear shifting.
Planetary gearbox
* Consists of gears that allow the automatic transmission to change the gear ratio.
Friction discs
* Connect and disconnect the elements of the planetary gearbox to change gears.
Gear shift drum
* Controls the position of the friction discs.
Automatic transmission housing
* Contains all automatic transmission components.
Gear shift valves
* Hydraulic devices that control the flow of fluid into the automatic transmission, determining which gear will be engaged.
Oil pump
* Creates the fluid pressure necessary for the operation of the automatic transmission.
Hydraulic accumulator
* Smoothes out fluid pressure fluctuations.
Friction tape
*Additionally used to engage gears on some models.
Electrical control unit (ECU)
* Controls the operation of the automatic transmission, controlling the gear shift valves and other components.
Sensors
* Provide the ECU with information about vehicle speed, gear selector position and other parameters.
Operating modes
* P (Parking): Locks the output shaft of the automatic transmission.
* R (Reverse): Engages reverse gear.
* N (Neutral): No gear engaged.
* D (Drive): Engages all forward gears in automatic mode.
* 2: Limits the automatic transmission to engage only the first two gears.
* L: Limits the automatic transmission to engage only first gear.