What the P0521 code means?
Every modern vehicle is outfitted with a PCM (Powertrain Control Module). This computer controls a number of sensors, controls and other electronic components. One such sensor is the oil pressure sensor which detects how much mechanical oil pressure is present in the engine. It then sends this reading to the PCM in the form of a voltage value.
What causes the P0521 code?
Low oil level in the engine
Old dirty oil (overdue for an oil change)
Low oil pressure
Faulty wiring or connection/connector in the oil pressure sender circuit
Faulty oil pressure sender/sensor
What are the symptoms of the P0521 code?
The service engine soon lamp and/or red low engine oil pressure warning lamp may be illuminated and a code will be stored in the PCM. Failure to turn the engine off during a low oil pressure situation will cause engine noise and possibly catastrophic engine failure.
Common mistakes when diagnosing the P0521 code
The oil pressure sensor may need to be replaced, but a mechanic shouldn't do so until they carry out a full inspection. While this may actually clear the code and make the dashboard light go away, the engine could have already been damaged. By not inspecting this, the mechanic will send their customer back on the road with a huge problem under the hood.
What repairs can fix the P0521 code?
As we said earlier, this code should be addressed ASAP because if there is a mechanical problem like actual low oil pressure it can be a major and expensive repair a good reminder to owners that their vehicle needs oil changes every 3,000 miles.