Oil pressure sensor fault; ECU logs implausible oil pressure reading; engine may not start or may derate.

Safety: Ensure engine is off and cannot start automatically before removing any sensor.

• Locate sensor: The oil pressure sensor is usually mounted on the engine block near the oil filter housing.
• Inspect connector and wiring: Disconnect the plug and check for oil contamination, corrosion, or damaged pins. Clean and reseat. Trace the harness for chafing or crushed sections and repair as needed.
• Test with mechanical gauge: Temporarily install a mechanical gauge to verify actual oil pressure. If pressure is normal but the ECU reading is not, replace the sensor with a Volvo Penta-approved part.
• Clear codes and retest: After replacement, clear the fault codes and monitor oil pressure via diagnostics. Persistent faults may indicate ECU input issues requiring professional service.