K 3500 Truck 4WD V8-393 6.5L DSL Turbo (1993)
Pressure Control Solenoid (PCS): Description and Operation
Force Motor Circuit
PURPOSE
The pressure control solenoid takes the place of the throttle valve or vacuum modulator used on past transmissions. It controls transmission line
pressure.
OPERATION
The pressure control solenoid controls line pressure by moving a pressure regulator valve against spring pressure. The PCM/TCM varies line
pressure based on engine load. Engine load is calculated from various inputs especially the TPS switch. Line pressure is actually varied by
changing the amperage applied to the pressure control solenoid from 0 amps at high pressure to 1.1 amps at low pressure. Current to the pressure
control solenoid is periodically pulsed to prevent contamination from sticking the pressure regulator valve.
LOCATION
The pressure control solenoid is attached to the valve body.
