Oil Pressure Gauge
WARNING: This page is about a different car, the 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster is hardwired to the oil pressure sender unit. The instrument cluster monitors the oil pressure data and commands the oil pressure gauge indication with a corresponding movement of the pointer. The oil pressure indicator sender unit consists of a diaphragm and contact points. When the engine is started, the contact points close, causing the gauge to indicate normal oil pressure. With no oil pressure, the contacts open and the gauge indicates low oil pressure.