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

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

N1-N4:

N4-N7:

N8:

Normal Operation
The oil pressure switch is a normally open switch that is hardwired to the instrument cluster through circuit CMC24 (GY). When the oil pressure is within normal ranges, the oil pressure switch closes and grounds the signal to the instrument cluster, and the instrument cluster turns off the low oil pressure warning indicator. When engine oil pressure is low, the oil pressure switch opens, removing the ground signal to the instrument cluster, and the instrument cluster illuminates the low oil pressure warning indicator.

Possible Causes
- Circuit CMC24 (GY) open, short to ground or voltage
- Circuit CMC24 (WH/RD) open (4.0L)
- Base engine concern
- Oil pressure switch
- Instrument cluster