Oil Level Sensor: Description and Operation

PURPOSE
The Powertrain Control Module (PCM) checks the engine oil pressure continuously. If the oil pressure switch indicates low oil pressure at any time, the PCM will send information through serial data to the instrument cluster to turn "ON" the "Low Oil Pressure" telltale.

OPERATION
The oil level switch is an assembly containing a reed switch and magnetic float. When the oil level is normal, the float rests near the reed switch, causing the switch to close. When the oil level is low, the float rests away from the reed switch and the switch opens.

The oil level switch is mounted in the engine oil pan where it can monitor the engine oil level. The oil level switch supplies a ground signal to the PCM when the engine oil level is above a specific level. If the engine oil level falls below this level, the oil level switch opens and the PCM sends information through serial data to the instrument cluster to turn "ON" the check oil telltale.