Abstract: A shift range control system for an automatic transmission, comprising: a first range switching mechanism for selecting a shift range mechanically; and a second range switching mechanism for outputting an electric signal, while a predetermined shift range is being selected by the first range switching mechanism, to switch the shift range electrically. Further comprised is a return switch mechanism for releasing the shift range, which is lower by two or more steps than the predetermined shift range selected by the first range switching mechanism, to switch the same to the predetermined shift range. Thus, it is possible to improve the conveniences for switching the shift range of the automatic transmission by the electric operation.

Abstract: A controller for an automatic transmission includes a sensor for detecting a vehicle operating condition, a transmission for changing a rotational ratio of drive and driven shaft, and an ordering mechanism for ordering shift change to drive the transmission based on the operating condition detected by the sensor. Also provided are a cornering mechanism for detecting vehicle cornering, an accelerating detection mechanism for detecting vehicle acceleration, and an inhibiting mechanism for inhibiting shift down to lower the rotational ratio of drive and driven shaft in the transmission by the controller in case both vehicle cornering detected by the cornering mechanism and vehicle acceleration detected by the accelerating detection mechanism are equal to or greater than the first and second preset values, respectively.