Circuit/System Testing

With the ignition ON, install a scan tool, and observe the Engine Oil Pressure Switch parameter in the ECM/PCM Engine Data list.

• If the Engine Oil Pressure Switch displays Ok, replace the instrument panel cluster (IPC).
• If the Engine Oil Pressure Switch displays Low, then disconnect the engine oil pressure switch, start the engine, and observe the Engine Oil Pressure Switch parameter.
• If the Engine Oil Pressure Switch displays Ok, check for poor connection at the harness connector of the engine oil pressure switch.
• If the harness connector is normal, replace the engine oil pressure switch.
• If the Engine Oil Pressure Switch displays Low, check the signal circuit of the engine oil pressure switch for a short to ground.
• If the signal circuit tests normal, check for a poor connection at the harness connector of the ECM.
• If the harness connector is normal, replace the ECM/PCM.