Pressure Control Solenoid Valve - Normally Low
WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
A normally low solenoid valve has minimum pressure with no current. As the current increases, the pressure increases.