Oil Pressure Sensor: Description and Operation

PURPOSE
The oil pressure switch will supply power to the fuel pump if the fuel pump relay should fail to supply power.

OPERATION
As a backup system to the fuel pump relay, the fuel pump also can be turned "ON" by the oil pressure sensor/switch. The oil pressure sender has two internal circuits. One operates the oil pressure indicator or gage in the instrument cluster and the other is a normally open switch which closes when oil pressure reaches about 28 kPa (4 psi). If the fuel pump relay fails, a Code 54 will be set in the Electronic Control Module (ECM) and the oil pressure switch runs the fuel pump.