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Transmission Pressure Control Solenoid Valve (Force Motor)






A transmission Pressure Control Solenoid Valve (PC Sol valve), also known as a force motor 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 Sol. 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 Sol. valve; This advanced control method assures instantaneous control of line pressure when changes occur in the TPS and adaptive learning.

The resistance on the PC Sol. valve should measure 3.0 - 7.0 ohms when measured at 20 - 100° C (68 - 212° F).