Abstract: An engine driven auxiliary device consumes engine power and thus reduces the amount of torque supplied to an automatic transmission. In the automatic transmission, a line pressure control and/or a shift control is performed on a predetermined parameter that is employed as reflecting an instantaneous amount of engine torque supplied to the automatic transmission. There occurs a deviation of this predetermined parameter from the actual amount of torque supplied to the automatic transmission when the auxiliary device is in operation. Thus, a sensor output of a throttle opening degree sensor is corrected when the auxiliary device is in operation and then set as the predetermined parameter although the sensor output unaltered is set as the predetermined parameter when the auxiliary device is not in operation.

Abstract: An apparatus for use with a transmission including an input shaft, and an oil pump rotatable in synchronism with the input shaft to detect a speed of rotation of the input shaft. The apparatus comprises a pressure sensor sensitive to an oil pressure discharged from the oil pump for producing an electrical signal indicative of a sensed pressure. The electrical signal is utilized to detect the input shaft rotation speed.