J2000/Sunbird V6-191 3.1L VIN T MFI (1994)
Power Steering Pressure Switch Circuit
Circuit Description:
The Power Steering Pressure (PSP) 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. The PCM will increase the idle air rate and disengage the A/C relay.
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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.
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A switch that will not open, or a CKT 495 shorted to ground, may affect idle quality and will cause the A/C relay to be de-energized.
Test Description: Number(s) below refer to circled number(s) 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 displayed.
2. Checks to determine if CKT 495 is shorted to ground.
3. This should simulate a closed switch.
