Engine Oil Pressure Switch
The PCM applies battery voltage through a pull up resistor to the Engine Oil Pressure switch circuit. The PCM monitors the applied voltage on the Engine Oil Pressure switch circuit. If the ignition is turned ON, with the engine not running, or engine oil pressure is below 35 kPa (5 psi), the engine oil pressure switch grounds the PCM voltage input. The PCM sends the engine oil pressure information via Class 2 Serial Data to the Instrument Panel Cluster (IPC). The IPC controls the engine oil pressure indicator.