DTC P1189: Engine Oil Pressure Switch Circuit: Description

Engine oil pressure switch closes (signal circuit is low) with low oil pressure and opens (signal circuit is high) with oil pressure above 4.5 psi. Powertrain Control Module (PCM) monitors oil pressure switch signal circuit and sends a class 2 message to Body Control Module (BCM) indicating switch status. BCM sends a message via Serial Peripheral Interface (SPI) to instrument cluster in order to illuminate low oil pressure indicator.