Circuit/System Description

The engine oil level switch is a normally closed switch that opens when there is a low engine oil condition. When the switch is open the engine control module (ECM) will detect a high signal voltage input. During a low engine oil condition the ECM sends a high speed GMLAN message to the body control module (BCM). The BCM then sends a message via low speed GMLAN to the instrument panel cluster (IPC) requesting illumination of the ENGINE OIL LOW ADD OIL message in the driver information center (DIC).