According to Repair Pal, the oil pressure sensor is usually found on the bottom, right side of an engine, between the oil filter and the oil pan. The oil pressure sensor, also known as the oil pressure switch or sender, is located differently depending on the make of the vehicle.
According to Autos.com, the oil pressure sensor detects the pressure at which the oil pump pumps engine oil. An oil pump that is in good functioning order has a pressure of 20 to 40 pounds per square inch. If the pressure falls below this level, serious and permanent engine damage ensues. Some automobiles have both electrical and mechanical oil pressure gauges incorporated into the dashboards, while others feature signal lights. The oil pressure warning system in the car warns the driver to any problems detected by the sensor.
According to AutoZone, a malfunctioning oil pressure sensor is commonly the source of a low oil pressure reading. If the oil pressure in the main gallery is not low but the oil pressure sensor is, the sensor is most likely broken and needs to be replaced. A mechanic can look for a loose or damaged connection in the sensor. A mechanic can check for indicators of an oil leak if the oil level is low.