P0520: Engine oil pressure sensor or switch circuit

The computer sees a fault in the oil pressure sensor circuit. The driver may see the oil warning or a gauge that reads wrongly.

Likely causes, most common first

  • Faulty oil pressure sensor
  • Damaged wiring or connector
  • Oil leak at the sensor
  • Real low oil pressure

Parts usually involved

  • Oil pressure sensor
  • Sensor connector
  • Engine oil

Test before you replace

Check the oil level and measure actual oil pressure with a mechanical gauge, then test the sensor circuit.

General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.

Run your jobs from your phone
Show the customer the problem and get their yes in seconds.
Sign up free