Hydraulic control apparatus of an automatic

A in a first Solenoidrelaisventil (23) entered Modulierdruck is input of a first clutch (21) at a normal time and when an in oil chambers (23r1 and 23r2) inputted print is high in an oil chamber (21r1), and in a second Solenoidrelaisventil (24) entered Modulierdruck is input by a solenoid valve (S1), which is turned on at the normal time and when the in the oil chambers (23r1 and 23r2) input pressure is low, which means that the first clutch (21 ) is held in a normal time position when a (in an oil chamber 21r3) increases inputted signal pressure suddenly. Since an error time no Modulierdruck in the oil chamber (21r1) is input, the first clutch (21) is switched to an error time position, thereby allowing a D-range pressure in the hydraulic servo can be input (41 and 42) and a line pressure in a hydraulic servo (43) can be entered.