The Power Steering Pressure (PSP) switch is located at the high pressure line outlet fitting of the
Power Steering Pump. When steering system pressure reaches a high-pressure set point, the PSP switch closes and sends a signal to the PCM, which uses it to maintain engine idle speed during parking maneuvers. The operation of the PSP switch should be checked if the engine stalls during parking or idles continuously at high rpm. To perform the check, loosen the right front wheel lug nuts, raise the vehicle, and support it securely on jackstands. Remove the right front wheel and the right front fender apron seal by taking out the three screws and the plastic inner seal from the fender well. Disconnect the PSP switch connector and connect an ohmmeter to the terminal and the switch body. Start the engine and let it idle, then turn the
Steering Wheel to point the front wheels straight ahead and read the ohmmeter, which should indicate no continuity (infinite resistance). Next, turn the steering wheel to each side; the PSP switch should close as the wheel nears the steering stop on each side, and the meter should indicate continuity (zero ohms). If the switch fails either test, it should be replaced. To replace it, raise the vehicle and support it securely on jackstands, then disconnect the cable from the negative battery terminal. Disconnect the electrical connector from the switch and unscrew the switch from the fitting on the steering pump, removing the old O-ring and installing a new one. Finally, install and connect the new switch, lower the vehicle to the ground, bleed air from the power steering system, and add fluid as required.