Rocker Arm Oil Pressure Switch
WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
Rocker arm oil pressure switch detects oil pressure when the rocker arm oil control solenoid is ON. The oil pressure switch input enables the PCM to monitor the operation of the rocker arm oil control solenoid.