Skyhawk L4-121 2.0L Turbo VIN M FI (1987)
Wiring Diagram for Chart C-1E Power Steering Pressure Switch Check
CHART C-1E POWER STEERING PRESSURE SWITCH (PSPS) DIAGNOSIS
Circuit Description:
The power steering pressure switch is normally open to ground, and CKT from D13 will be near 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 from D13 to read less than 1 volt. The ECM will increase the idle air rate and disengage the A/C relay. A pressure switch that will not close,
or an open CKT from D13 may cause the engine to stop when power steering loads are high. A switch that will not open, or CKT D13 shorted to
ground, may affect idle quality and will cause the A/C relay to be de-energized.
Test Description: Numbers below refer to circled numbers on the diagnostic chart.
1.
Different makes of "Scan" tools may display the state of this switch in different ways. Refer to "Scan" tool operator's manual to determine how this
input is indicated.
2.
Checks to determine if CKT from D13 is shorted to ground.
3.
This should simulate a closed switch.
