Century Estate Wagon L4-151 2.5L VIN R TBI (1987)
Fig. 008 Wiring Diagram for C-1E-1 Power Steering Pressure Switch (PSPS) Diagnosis
CHART C-1E-1
POWER STEERING PRESSURE SWITCH (PSPS) DIAGNOSIS
2.0L "J & L" SERIES
2.5 "A & N" SERIES
FUEL INJECTION (TBI)
Circuit Description: The power steering pressure switch is normally open to ground, and CKT 495 will be near the battery voltage.
Turning the steering wheel increases power steering oil pressure and its load on an idling engine. The pressure switch will close before the load can
cause an idle problem.
Closing the switch causes CKT 495 to read less than 1 volt and the ECM will increase the idle air rate.
A pressure switch that will not close, or an open CKT 495 or 450, may cause the engine to stop when power steering loads are high.
A switch that will not open, or a CKT 495 shorted to ground, may affect idle quality.
Test Description: Numbers below refer to circled numbers on Diagnostic Chart
1.
Different makes of "Scan" tools may display the state of this switch in different ways. Refer to "Scan" tool upgrading to determine how this input
is indicated.
2.
Checks to determine if CKT 495 is shorted to ground.
3.
This should simulate a closed switch.
