Power Steering Pressure Switch: Description and Operation

Power Steering Pressure Switch:

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 air conditioning compressor clutch disengagement. A signal is also sent to the ECM. The ECM uses this signal for idle speed control. A Scan tool should read "off" normally, and "on" with high pressure.