OBD-II code guide

P0520 Engine Oil Pressure Sensor Circuit

P0520 means the oil pressure sensor or circuit signal is not believable to the engine computer.

What it means

The computer sees an electrical problem with the oil pressure monitoring circuit, but real oil pressure must still be treated seriously.

Common symptoms

  • Oil pressure warning
  • Check engine light
  • Gauge reading wrong
  • Possible ticking
  • Possible no drivability change

Likely causes

  • Faulty oil pressure sensor
  • Low oil level
  • Wiring issue
  • Poor connector contact
  • Real oil pressure problem

First checks

  • Check oil level immediately.
  • Do not assume it is only a sensor if engine noise is present.
  • Verify actual pressure with a mechanical gauge when needed.
  • Inspect for oil leaks around the sensor.