P0520: Oil pressure sensor/switch circuit malfunction
Electrical fault in the oil pressure sensor circuit. Usually the connector, the wiring or the sensor itself, but low oil pressure must be ruled out.
| Code | P0520 |
|---|---|
| System | Engine and transmission |
| Group | P05xx, Speed, idle and auxiliary inputs |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P0520 means
The oil pressure sensor or switch tells the car whether the engine has enough oil pressure to stay lubricated. Some cars use a simple switch, others a sensor that measures pressure. This code means its circuit is giving an invalid signal, so the car cannot monitor pressure properly.
Most common causes
- Loose, dirty or oil-soaked sensor connector
- Broken or bare sensor wire, often from engine heat
- Faulty oil pressure sensor, or one leaking oil internally
- Low oil level or genuinely low pressure
- Instrument cluster or ECU fault, which is rare
Symptoms
- Oil pressure light on, flickering or never coming on
- Oil pressure gauge reading oddly, if fitted
- Engine warning light on
Can you drive with P0520?
With care If the oil level is correct and the engine makes no unusual noises, you can drive carefully to a garage. But without a reliable reading you will not know if pressure drops, so do not put it off.
Open the bonnetthe in-depth explanation
How to check it
First check the oil level on the dipstick, on level ground and with the engine cold. If it is fine, check the sensor connector, usually on the block near the oil filter. A garage can confirm actual pressure with a mechanical gauge.
How to read and clear P0520 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0520 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P051C The sump pressure sensor gives a lower signal than normal
- P051D The sump pressure sensor gives a higher signal than normal
- P051E The sump pressure sensor fails now and then
- P051F The positive sump ventilation filter restriction is not working properly
- P0521 Oil pressure sensor/switch range/performance
- P0522 Oil pressure sensor/switch low voltage
- P0523 Oil pressure sensor/switch high voltage
- P0524 Engine oil pressure too low
- P0500 Vehicle speed sensor malfunction
- P0501 Vehicle speed sensor range/performance
- P0502 Vehicle speed sensor circuit low input
- P0503 Vehicle speed sensor intermittent, erratic or high
To understand it properly
We explain how that system works, with drawings and no waffle, in our mechanics guide: Oil and lubrication.
What does code P0520 mean?
The oil pressure sensor or switch tells the car whether the engine has enough oil pressure to stay lubricated. Some cars use a simple switch, others a sensor that measures pressure. This code means its circuit is giving an invalid signal, so the car cannot monitor pressure properly.
Can you drive with P0520?
If the oil level is correct and the engine makes no unusual noises, you can drive carefully to a garage. But without a reliable reading you will not know if pressure drops, so do not put it off.
How do you clear P0520?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0520 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
