WOMS
P code powertrain High severity

P0520 Engine Oil Pressure Sensor/Switch Circuit Malfunction

The OBD2 code P0520 indicates a malfunction in the engine oil pressure sensor or switch circuit, which may affect the engine's ability to monitor oil pressure accurately

Definition

The OBD2 code P0520 indicates a malfunction in the engine oil pressure sensor or switch circuit, which may affect the engine's ability to monitor oil pressure accurately

Common causes

  • Faulty engine oil pressure sensor
  • Wiring issues (damaged, frayed, or corroded wires)
  • Poor electrical connections
  • Faulty engine control module (ECM)
  • Low engine oil level or pressure
  • Oil sludge or contamination
  • Faulty oil pump

Common misdiagnoses

  • Faulty oil pump
  • Low oil level or oil quality issues
  • Engine wear or damage
  • Electrical issues (wiring or connectors)
  • Faulty engine control module (ECM)
  • Oil pressure gauge malfunction
  • Incorrect oil viscosity
  • Oil filter blockage

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide additional context and help identify related issues

  2. 2. Inspect the Oil Pressure Sensor

    Visual Inspection: Check the oil pressure sensor for any visible damage, corrosion, or loose connections

  3. 3. Wiring and Connectors

    Inspect the wiring harness and connectors for fraying, breaks, or corrosion. Ensure that the connections are secure

  4. 4. Test the Oil Pressure Sensor

    Resistance Test: Use a multimeter to measure the resistance of the oil pressure sensor. Compare the readings to the specifications provided in the vehicle’s service manual

  5. 5. Voltage Test

    With the ignition on (engine off), check the voltage at the sensor connector. It should match the specifications in the service manual

  6. 6. Check Engine Oil Level and Condition

    Ensure that the engine oil is at the correct level and in good condition. Low oil levels or dirty oil can affect oil pressure readings

  7. 7. Inspect the Engine Oil Pressure

    If possible, use a mechanical oil pressure gauge to check the actual oil pressure. This will help determine if the issue is with the sensor or if there is a genuine oil pressure problem

  8. 8. Check for Ground Issues

    Ensure that the oil pressure sensor has a good ground connection. A poor ground can lead to incorrect readings and trigger the P0520 code

  9. 9. Examine the Engine Control Module (ECM)

    In rare cases, the issue may lie with the ECM itself. Check for any software updates or known issues related to the ECM

  10. 10. Clear the Code and Test Drive

    After performing the above checks and repairs, clear the trouble code using the OBD-II scanner. Take the vehicle for a test drive to see if the code returns

  11. 11. Replace the Oil Pressure Sensor

    If all tests indicate that the sensor is faulty, replace the oil pressure sensor with a new one. Ensure that the replacement part is compatible with your vehicle

  12. 12. Consult a Professional

    If you are unable to resolve the issue after these steps, it may be best to consult a professional mechanic for further diagnosis.Additional Tips: - Always refer to the vehicle’s service manual for specific testing procedures and specifications. - Safety first: Ensure the engine is cool and the vehicle is on a flat surface before performing any inspections or repairs. By following these steps, you should be able to diagnose and address the P0520 code effectively