| 摘要 |
A control system of a downshift by an automatic transmission having an improved shift feeling by controlling pressure fed to a kickdown servo brake comprises a throttle valve sensor, an input shaft rpm sensor, an output shaft rpm sensor, a transmission control unit for outputting a control signal for a second-to-first speed shift after reducing hydraulic pressure fed to a predetermined state using every duty pattern when the vehicle is in the state of a second-to-first downshift, or a control signal for a second-to-first speed shift after the third-to-second speed shift is completed when the vehicle is in the state of a third-to-first speed shift, and first and second transmission control solenoid valves, and a hydraulic pressure control solenoid valve for changing the state of hydraulic pressure fed to every friction member. <IMAGE> |
