Toyota Celica 1993 AT200 series Repair Manual page 650

sR-31
STEERING - POWER STEERING
O P E R A T I O N
O P E R A T I O N
NEUTRAL (STRAIGHT _AHEAD) POSITION
Fluid from the pump is sent to the control valve. lf the control valve is in thE noutral position, all
the fluid will flow through the control valve into the relief port and back to the pump. At this timo,
hardly any prossurs is created and because th€ pressure on the cylinder piston is equal on both
s i d e s , t h e p i s t o n w i l l n o t m o v e i n e i t h e r d i r e c t i o n .
W H E N T U R N I N G
When the steering main shaft is turned in eithsr direction, the control valve also moves, closing
one of the fluid passages. The other passag€ then opens wider. causing a change in fluid flow
volume and, at th€ same time, a differential pressure is cr€atod between both sides of the piston.
Consequently, the piston moves in the direction of the lowor pressur€ so that ths fluid in the
cvlinder is forced back to the pump through the control valve.