Oil Pressure Warning Lamp/Indicator: Description and Operation

The operation of individual indicators is stated below. For indicators not listed below (for instance, door ajar, seat belt, etc.), see the system indicated by the circuit schematic diagrams.

Oil Pressure Indicator
Battery voltage is applied to the indicator bulb from fuse 10 with the ignition in ON or START. When the oil pressure is low, the oil pressure switch closes, providing a ground for the indicator bulb. Due to the oil pressure not present when the engine is not running or ignition ON, the pressure switch remains closed.

CHECK ENGINE Indicator
Battery voltage is applied to the indicator bulb from fuse 10 with the ignition in ON or START. The ground of the indicator is controlled by the engine control module. The control module will light the indicator when the engine is not running or when it detects a problem.