Test I: The Low Oil Pressure Warning Indicator Is Never/Always On

PINPOINT TEST I: THE LOW OIL PRESSURE WARNING INDICATOR IS NEVER/ALWAYS ON

I1-I2:

I3-I5:

Normal Operation
The engine oil pressure switch is a normally closed switch that is hardwired to the instrument cluster through circuit 253 (DG/WH). When the oil pressure is within normal ranges, the engine oil pressure switch opens, interrupting the ground signal to the instrument cluster and turns the low oil pressure warning indicator off. When engine oil pressure is low, the engine oil pressure switch closes, supplying the ground to the instrument cluster, and illuminates the low oil pressure warning indicator.

Possible Causes
- Circuit 253 (DG/WH) open, short to ground or voltage
- Engine oil pressure switch
- Low engine oil pressure
- Instrument cluster