Hydraulic pressure control device

A hydraulic pressure control device for an automatic transmission that performs a gear shift by switching between engagement and disengagement of a plurality of friction engagement elements, the hydraulic pressure control device comprising:

• a plurality of solenoid valves configured to switch between engagement and disengagement of the friction engagement elements by switching between supply and non-supply of hydraulic pressures to the friction engagement elements, the solenoid valves being provided corresponding to the friction engagement elements, respectively;
• and
• a control device configured to switch between supply and non-supply of the hydraulic pressures to the friction engagement elements by supplying a predetermined control current to the solenoid valves, wherein
• the control device supplies a fixation preventing current lower than the control current to at least one of the solenoid valves in a disengagement state of the friction engagement elements,
• when it is determined that no switching instruction is present, it is determined whether the friction engagement elements are being engaged, and whether the friction engagement elements are being engaged is determined based on a detection signal from an engagement hydraulic pressure sensor,
• when it is determined that the friction engagement elements are engaged, the supply of the predetermined control current for engaging the friction engagement elements is maintained, and
• when it is determined that the friction engagement elements are not engaged, the control current for engaging the friction engagement elements is not supplied, the supply of the fixation preventing current to an engagement hydraulic pressure control valve is maintained.