System Description

Fluid Flow Diagram

The reservoir supplies power steering fluid to the pump; the pump pressurizes the fluid to about 8000 kPa (1200 psi), and delivers it through a high pressure hose to the control unit on the gearbox.
The control valve (in the control unit) controls the direction of the turn by shifting fluid to the left or right side of the piston on the rack (in the power cylinder). The cut-off valve, also in the control unit, controls the amount of assist by regulating the stroke of the control valve.
Fluid returning from the power cylinder flows back through the control valve and out to the reservoir through the cooler.