Pressure Control Solenoid (PCS) Valve
A transmission pressure control solenoid (PCS) valve, is a three-port, spool valve, electronic pressure regulator. The solenoid controls pressure based on a flow of current through its coil-winding. The solenoid controls main line pressure by moving a pressure regulator valve against spring pressure.
The position of the PC solenoid valve is controlled by a combination of two methods: high side control and low side control. One terminal of the solenoid receives a fixed frequency signal of 614.0 Hz. This signal varies in positive (+) duty cycle. This feed circuit is called Force HI.
The opposite terminal of the transmission pressure control solenoid is called Force LO. Force LO provides a ground for the solenoid.
This combination of Force HI and Force LO circuitry controls the actual current through the PC solenoid valve. This advanced control method assures instantaneous control of line pressure when changes occur in the TP sensor and adaptive learning.
The resistance on the PC solenoid valve should measure 3.0-8.0 ohms when measured at 20°C (68°F).