A low oil pressure sensor monitors the oil pressure in the engine and alerts the driver when the pressure is low, signaling that the engine is low on oil. Low engine oil is potentially catastrophic, and the driver should check the oil level immediately and fill it if necessary.
The oil pressure sensor is located inside a major oil passage and triggers the oil pressure warning light if the pressure drops below a certain level. Low pressure causes engine parts to start rubbing together, which can cause a total engine failure in seconds. Engine oil pressure sensors in cars equipped with a powertrain computer are sometimes equipped with an emergency engine shutdown feature that disables the engine if the oil pressure is too low.