Power Steering Pressure Switch: Description and Operation

Pressure Switch
When hydraulic pressure reaches 3430 kPa (500 psi), the pressure switch of the power steering pump closes causing the Powertrain Control Module (PCM) to actuate the throttle valve, which increases the engine rpm to prevent the overload-induced engine speed slow down. The switch opens when hydraulic pressure drops to 2940 kPa (430 psi).