Oil Pressure Warning Lamp/Indicator: Description and Operation

Circuit Description

Check Engine & Oil Pressure Indicator
Battery voltage is applied to the indicator bulb from fuse 2 with the ignition switch in ON or START. The ground of the check engine 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. When the oil pressure is low, the oil pressure switch closes, providing a ground for the oil pressure indicator bulb.