POWER-ASSISTED STEERING SYSTEM
2A–9
The hydraulic pump is vane-type design. The
submerged pump has housing and internal parts that
are inside the reservoir and operate submerged in oil.
There are two bore openings at the rear of the pump
housing. The larger opening contains the cam ring,
pressure plate, thrust plate, rotor and vane assembly,
and end plate. The smaller opening contains the
pressure line union, flow control valve and spring.
The flow control orifice is part of the pressure line union.
The pressure relief valve inside the flow control valve
limits the pump pressure.
Pressure Switch
When hydraulic pressure reaches 3430 kPa (35 kg/cm
2
/
500 psi), the pressure switch of the power steering
pump closes causing the Engine Control Module (ECM)
to actuate the idle air control valve, which increases the
engine rpm to prevent the overload-induced engine
speed slow down. The switch opens when hydraulic
pressure drops to 2940 kPa (30 kg/cm
2
/430 psi).
Steering Column
431RY00009
WARNING: TO AVOID DEPLOYMENT WHEN
TROUBLE-SHOOTING THE SRS SYSTEM, DO NOT
USE ELECTRICAL TEST EQUIPMENT, SUCH AS
BATTERY-POWERED OR A/C-POWERED
VOLT-METER, OHMMETER, ETC., OR ANY TYPE
OF ELECTRICAL EQUIPMENT OTHER THAN
SPECIFIED IN THIS MANUAL. DO NOT USE A
NON-POWERED PROBE-TYPE TESTER.
INSTRUCTION IN THIS MANUAL MUST BE
FOLLOWED CAREFULLY, OTHERWISE PERSONAL
INJURY MAY RESULT.
When servicing a vehicle equipped with Supplemental
Restraint System, pay close attention to all WARNINGS
and CAUTIONS.
For detailed explanation about SRS, refer to Restraints
section.