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

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


D1-D2:






D2-D4:






D5-D7:






Normal Operation
The oil pressure switch is a normally open switch that is hardwired to the smart junction box (SJB) through circuit 1308 (BN/OG). When the oil pressure is within normal ranges, the oil pressure switch closes, grounding the signal to the SJB. The SJB then sends a command signal to the instrument cluster through the communication network, to turn off the oil pressure warning indicator. When engine oil pressure is low, the oil pressure switch opens, removing the ground to the SJB. The SJB sends a low oil pressure command to the instrument cluster through the communication network to illuminate the oil pressure warning indicator.

DTC C1284 - sets if circuit 1308 (BN/OG) is shorted to ground, with the engine off, during the self-test.

Possible Causes
- Circuit 1308 (BN/OG) open or short to ground
- Oil pressure switch
- SJB
- Instrument cluster