P0520: Engine Oil Pressure Sensor/Switch Circuit
The engine computer has found an electrical problem with the oil pressure sensor or switch circuit.
What P0520 means
The oil pressure sensor or switch screws into an oil passage and reports pressure to the engine computer or gauge. P0520 is a circuit code, meaning the computer sees a signal that is electrically out of range, such as an open or shorted wire, rather than a measured low pressure. A failed sensor or switch is the most common cause, and oil leaking past the sensor into its connector is a known problem on some engines. Even so, KBB is firm that you should not drive with oil pressure codes until they are checked, because the risk is too high: if oil pressure really is low, engine bearings can be ruined in minutes. The right first step is checking the oil level. Then a shop screws a mechanical gauge into the sensor port and measures real oil pressure at idle and at higher RPM. If pressure is good, they test the sensor circuit and replace the sensor. If pressure is low, the problem is the oil pump or engine wear.
Common symptoms
- Check engine light on
- Oil pressure light on or flickering
- Oil pressure gauge reading zero or maxed out
- No other symptoms if only the sensor is bad
- Engine noise if pressure is truly low
Most common causes
- Faulty oil pressure sensor or switch
- Damaged or corroded sensor wiring or connector
- Oil leaking into the sensor connector
- Low engine oil level
- Real low oil pressure from a worn oil pump or engine
What to check yourself first
Check the oil level on the dipstick right away. If it is low, top it up with the correct oil. Look for oil leaking from or around the sensor and inside its connector. Do not keep driving if the oil light stays on or the engine knocks.
Typical fixes and what they cost
| Fix | Typical cost | Note |
|---|---|---|
| Replace oil pressure sensor | $207-$261 | Common fix once real oil pressure is confirmed with a mechanical gauge. |
| Electrical diagnosis to find a wiring or connector fault | $122-$179 | For wiring or connector faults. |
| Oil and filter change with the correct oil | $160-$188 | If the level is low or the oil is overdue. |
| Check engine light diagnosis at a shop | $125-$183 | Includes a mechanical oil pressure test, which is the only way to know pressure is safe. |
Typical US price ranges for parts and labor, not quotes. Your shop should confirm the cause with a diagnostic before replacing parts.
Related repair guides
- Kia Sorento Engine Recall: Which Years Get the KSDS Update and the 15-Year/150,000-Mile Warranty
- 2017-2018 Honda CR-V Oil Level Rising or Smells Like Gas? The 1.5T Oil Dilution Problem Explained
- 2010-2013 Chevy Equinox Burning Oil? Fix the 2.4L Engine or Sell It
- 2007-2009 Toyota Camry Burning Oil? What's Going On and What a Fix Costs Now
Related codes
- P0521 Engine Oil Pressure Sensor/Switch Range/Performance
- P0011 "A" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1)
- P0012 "A" Camshaft Position - Timing Over-Retarded (Bank 1)
- P0016 Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor A)
- P0562 System Voltage Low