P0521 – Engine Oil Pressure Sensor/Switch Range/Performance

Meaning:

When the PCM has seen an unexpected value in engine oil pressure sensor, the P0521 happens
The P0521 is triggered when the PCM has seen an unexpected value in engine oil pressure sensor

The PCM has seen an unexpected value in engine oil pressure sensor. The value could be fixed when it should fluctuate or simply out of the normal range.

Main Symptoms:

  • Check Engine Light comes on
  • Oil pressure gauge may read too low or too high
  • Oil pressure light may come on

Possible Causes:

  • Oil level in the engine is too low
  • Oil pressure is too low
  • Dirty oil
  • Faulty wiring to oil pressure sensor

Diagnostic Steps:

  • Check that oil level is not too low
  • Check that the right oil was used
  • Visually inspect all wiring to oil pressure sensor and check for open, short or broken wires
  • If you can, take the oil pressure reading and compare with the reading shown by the vehicle’s PCM. That should tell you if the problem is with oil pressure

Read More: OBD2 Codes List: Meaning, Fixes, and Free Download