Hydraulic control system

A hydraulic control system comprising (i) a linear solenoid valve configured to continuously change a hydraulic pressure, (ii) an ON-OFF solenoid valve configured to output and stop outputting the hydraulic pressure, and (iii) a hydraulically-operated frictional engagement device that is to be engaged with an engaging torque that is based on the hydraulic pressure supplied to the frictional engagement device,

• the hydraulic control system comprising:
• a hydraulic control circuit is configured such that a first hydraulic pressure as the hydraulic pressure that is regulated by the linear solenoid valve and a second hydraulic pressure as the hydraulic pressure that is outputted through an ON-OFF switching of the ON-OFF solenoid valve are suppliable to the same frictional engagement device, and such that the first hydraulic pressure is regulated by the linear solenoid valve to be within a predetermined pressure-regulation control range that is lower than the second hydraulic pressure;
• and
• an engagement control portion configured to supply the first hydraulic pressure to the frictional engagement device while causing the linear solenoid valve to regulate the first hydraulic pressure within the pressure-regulation control range,
• the engagement control portion being configured, in a state in which the frictional engagement device is placed in a predetermined engaged state based on the first hydraulic pressure, to supply the second hydraulic pressure to the frictional engagement device through the ON-OFF switching of the ON-OFF solenoid valve, such that the frictional engagement device is placed in a fully engaged state with the engaging torque based on the second hydraulic pressure.