Power Steering Pressure (PSP) Switch
WARNING: This page is about a different car, the 1997 Mazda Millenia. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect power steering pressure switch connector. Connect ohmmeter between PSP switch and ground. Start engine and operate at idle. Turn steering wheel from side to side and observe ohmmeter. Continuity should exist when steering wheel is turned. Continuity should not exist when steering wheel is straight ahead. If continuity is not as specified, replace PSP switch.