Engine Oil Pressure
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The instrument panel cluster (IPC) displays the engine oil pressure indicator as determined by the engine control module (ECM). The ECM monitors the engine oil pressure switch/sensor signal circuit to determine the engine oil pressure. The ECM sends the EOP information to the IPC via the serial data circuit. The IPC receives a serial data message from the BCM requesting display of the engine oil pressure indicator from the ECM.