P0520: Engine Oil Pressure Sensor/Switch Circuit Malfunction
17 vehicles · 9 makes · $50-$8,000 repair
Most Reported On
P0520 is an OBD-II diagnostic trouble code meaning “Engine Oil Pressure Sensor/Switch Circuit Malfunction.” This code indicates a general electrical fault in the circuit for the engine oil pressure sensor or switch. The computer monitors this circuit to know your oil pressure, and it has detected a signal that is missing, shorted, or otherwise out of the expected electrical range. This is typically a wiring or sensor problem rather than an actual loss of oil pressure, but because oil pressure is critical to engine life, it should never be ignored until confirmed. If oil pressure truly is low, serious engine damage can result. This code is most commonly reported on 1999-2008 Porsche 911 (Carrera, Carrera S, Carrera 4, Carrera 4S, Targa), 1997-2008 Porsche Boxster (Base, S), and 2006-2012 Porsche Cayman (Base, S, R), plus 14 other vehicles, with repair costs ranging from $50 to $8,000.
Common Causes
Typical Repair Cost
Based on 17 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0520, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (17)
2.7L V6 Engine Oil Sludge and Seizure
3.5L V6 Engine Oil Sludge and Consumption
3.5L V6 Excessive Oil Consumption
3.3L/3.8L V6 Engine Oil Leaks
FAQ
What does P0520 mean?
P0520 stands for "Engine Oil Pressure Sensor/Switch Circuit Malfunction." This code indicates a general electrical fault in the circuit for the engine oil pressure sensor or switch. The computer monitors this circuit to know your oil pressure, and it has detected a signal that is missing, shorted, or otherwise out of the expected electrical range. This is typically a wiring or sensor problem rather than an actual loss of oil pressure, but because oil pressure is critical to engine life, it should never be ignored until confirmed. If oil pressure truly is low, serious engine damage can result.
What are the most common causes of P0520?
The most common causes of P0520 are: Faulty oil pressure sensor or switch, Damaged, corroded, or loose wiring/connector at the sensor, Open or short in the sensor circuit wiring, Poor ground connection, Low engine oil level or genuinely low oil pressure, Failed PCM/ECM (less common). The specific cause varies by vehicle.
How much does it cost to fix P0520?
Repair costs for P0520 range from $50 to $8,000, depending on the vehicle and root cause.
Which vehicles are affected by P0520?
Au7o has documented P0520 across 17 vehicle models from 9 manufacturers: Cadillac, Chrysler, Dodge, Ford, Hyundai, Jeep, Kia, Porsche, Subaru.
Sources (12)
- manufacturerLN Engineering: Identifying and Fixing the Porsche IMS Bearing Problem
- manufacturerLN Engineering: IMS Bearing Problem Years in Porsche Boxster and 911
- mediaFerdinand: Porsche IMS bearing failure: settlement reached
- mediaWikipedia: Porsche Intermediate Shaft Bearing issue
- mediaMotronix: Porsche IMS Bearing Failure (996/997): A Guide for Owners
- manufacturerIMS Retrofit: IMS Bearing Problem Years
- mediaDodge Engine Oil Sludge Lawsuits - AboutLawsuits
- Forum2.7 Dodge Intrepid engine problem - Allpar Forums
- media2001 Dodge Intrepid Oil Sludge - CarComplaints
- owner-reportDaimlerChrysler 2.7L Engine Oil Sludge and Failure Reports
- owner-reportChrysler 2.7L Engine Sludge - Class Action Documentation
- media2001 Dodge Stratus Oil Sludge Engine Failure - CarComplaints
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.