Line Pressure Control Solenoid Valve
WARNING: This page is about a different car, the 2003 Saturn Vue and 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The line Pressure Control (PC) solenoid valve (normally high, 3-port linear pressure control solenoid) is a precision electronic pressure regulator that controls transaxle line pressure based on current flow through its coil windings. As current flow is increased, the magnetic field produced by the coil moves the solenoid's plunger further away from the exhaust port. Opening the exhaust port decreases the output fluid pressure regulated by the line pressure control solenoid valve, which ultimately decreases line pressure. The TCM controls the line pressure control solenoid valve based on various inputs including throttle position, transmission fluid temperature and gear state.