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

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

R1-R4:

R4-R7:

Normal Operation
The oil pressure switch is a normally open switch. The instrument cluster provides a reference voltage to the engine oil pressure switch through circuit CMC24 (GY). When the oil pressure is within normal ranges, the engine oil pressure switch closes to ground, pulling the reference voltage low in the instrument cluster. The instrument cluster senses the low voltage and turns off the low oil pressure warning indicator. When engine oil pressure is low, the engine oil pressure switch opens, removing the ground and sending the reference voltage back to the normal voltage in the instrument cluster. The instrument cluster senses the reference voltage high and turns on the low oil pressure warning indicator.

Possible Causes
- Circuitry
- Engine oil pressure switch
- Base engine concern
- Instrument cluster