Lumina V6-3.8L VIN K (1998)
Pressure Regulating Solenoid: Description and Operation
PRESSURE CONTROL SOLENOID VALVE
The Pressure Control Solenoid Valve (PC Sol. Valve) is a precision electronic pressure regulator that controls transmission line pressure based on
current flow through its coil windings. As current flow is increased, the magnetic field which is produced by the coil moves the solenoid's plunger
further away from the exhaust port. Opening the exhaust port decreases the output fluid pressure, which is regulated by the PC Sol. Valve. This
ultimately decreases line pressure. The PCM controls the PC Sol. Valve based upon various inputs including throttle position, fluid temperature, MAP
sensor, and gear state.
The PCM controls the PC Sol. Valve on a positive duty cycle at a fixed frequency of 292.5 Hz (cycles per second). Duty cycle is defined as the
percentage of time when current flows through the solenoid coil during each cycle. A higher duty cycle provides a greater current flow through the
solenoid. The high (positive) side of the PC- Sol. Valve electrical circuit at the PCM controls the PC Sol. Valve operation. The PCM provides a
ground path for the circuit, monitors average current, and continuously varies the PC Sol. Valve duty cycle in order to maintain the correct average
current flowing through the PC Sol. Valve.
The Pressure Control Solenoid Valve resistance should measure between 3.5 - 4.6 ohms when measured at 20°C (68°F).
