Test O

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

Test O1-O2:

Test O2-O4:

Test O5-O8:

Normal Operation
The engine oil pressure switch is a normally closed switch that is hardwired to the front electronic module (FEM) through circuit 8-GC21 (WH/GN). When the oil pressure is within normal ranges, the engine oil pressure switch opens, removing the ground signal to the front electronic module (FEM). The FEM, upon the removal of the engine oil pressure switch ground, sends a signal to the instrument cluster through the standard corporate protocol (SCP) communication network to turn off the oil pressure warning indicator. When oil pressure is low, the engine oil pressure switch closes, grounding circuit 8-GC21 (WH/GN) to the FEM. The FEM sends a low oil pressure signal to the instrument cluster through the SCP communication network, circuits 4-EG8 (GY/VT) and 5-EG8 (BU/WH), to turn on the oil pressure warning indicator.

Possible Causes
- circuit 8-GC21 (WH/GN) open, short to ground or power
- engine oil pressure switch
- FEM
- instrument cluster