Section 03-14: Engine Controls, Electronic
1994 Mustang Workshop Manual
DESCRIPTION AND OPERATION
Power Steering Pressure (PSP) Switch
The power steering pressure switch (PSP switch) (3N824) is:
A normally closed switch that opens as pressure increases.
Used to send a signal to the powertrain control module (PCM) (12A650) to adjust idle speed to compensate for the additional load on the engine.