Automatic transmission — general information (Mazda 121 (3))

The car can also be equipped with an automatic transmission type STX. V transmission type STX (CTX - Continuosly Variable Transaxle) the transmission of force from the engine occurs continuously, through a steel belt, which consists of hundreds of high-strength steel links. It provides a connection between the input shaft of the gearbox and the output shaft and moves in pairs of conical disks. These disks, which form pulleys, depending on the driving mode and the load of the car, are hydraulically compressed or moved apart. Accordingly, the transmission belt is lowered deeper or moved higher in the outward direction along the pulleys.

In this connection, the gear ratio changes steplessly. The hydraulic control unit of the gearbox type STX automatically selects the gear ratio so that the engine always operates in the optimal mode.

In order to accelerate faster, for example, when overtaking, the automatic transmission has a so-called "kickdown" mode switch, which is activated when the "gas" pedal is fully pressed. The "kickdown" device ensures that a lower gear ratio is selected on the transmission.

Discussing the operation of an automatic transmission and properly diagnosing faults requires experience with automatic transmissions and knowledge of how they work. Therefore, only adjustment of the shift control cable is described here. Maintenance Operations (checking oil level, changing oil) are described in the 6 corresponding chapter.