P0520 — Engine Oil Pressure Sensor/Switch Circuit Malfunction
Drive with caution — fix soon.
What P0520 means
This code means the computer detected a general fault in the engine oil pressure sensor or switch circuit. It's usually caused by a failed oil pressure sensor, damaged wiring, or a bad connector, but in rare cases it can reflect a genuine oil pressure problem. Testing actual oil pressure and replacing a faulty sensor or repairing the wiring typically resolves it.
Common symptoms
- Check engine light is on
- Oil pressure warning light on or flickering
- Inaccurate or erratic oil pressure gauge reading
- Oil light behaves oddly at idle or startup
- In some cases, no noticeable drivability change
Common causes
- Failed oil pressure sensor or switch
- Damaged or corroded wiring to the sensor
- Loose or corroded electrical connector
- Short or open in the oil pressure circuit
- Genuinely low oil pressure (less common)
Typical repair cost
$100 – $350
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0520 code?
Only after confirming your oil level and actual oil pressure are fine. If the oil warning light is on or flickering, stop and check immediately, because real low oil pressure can destroy an engine fast.
How much does it cost to fix a P0520?
Most repairs cost between $100 and $350. Replacing the oil pressure sensor is usually inexpensive, while diagnosing and repairing wiring faults can push the price up.
Is a P0520 code serious?
It's moderate, but it deserves attention because it affects your oil pressure warning. Usually it's just a sensor or wiring issue, but it should be checked to rule out a real oil pressure problem.
Does P0520 mean my oil pressure is low?
Not necessarily. It most often points to a sensor or wiring fault, but a mechanic should verify actual oil pressure with a manual gauge to be safe before assuming it's just electrical.