Lumina V6-191 3.1L VIN T MFI (1993)
Power Steering Pressure Switch: Description and Operation
Power Steering Pressure Switch
PURPOSE
To sense high pressure in the steering box and signal the ECM to adjust the idle speed accordingly.
OPERATION
The Power Steering Pressure Switch (PSPS) opens during high pressure power steering situations. When the power steering switch is open, power
to the A/C relay is shut "OFF," resulting in A/C compressor clutch disengagement. Also, a signal is sent to the ECM. The ECM uses this signal to
compensate for the additional engine load by moving the IAC valve.
