P0520 describes implausible oil-pressure sensor circuitry, but actual pressure must be proven safe first. Compare a mechanical gauge with scan data and test the reference, ground, signal and oil-contaminated connector. Bulletin 18-034-14 Rev. A lists 2013–2014 WK Grand Cherokee for a revised sensor branch with VIN/RRT verification. Other engines and years require their own sensor range and pressure specification.
Match the symptom
Select the closest observation. The result changes the first test; it does not name a part to replace.
Shut down and measure pressure.
What can set P0520—and how to separate it
The order below is evidence-driven, not a universal probability ranking. Vehicle year, repair history, companion codes and the operating condition in freeze frame change where diagnosis should begin.
| Possible cause | Evidence that supports it | First useful test |
|---|---|---|
| Oil-pressure sensor failure | Mechanical pressure normal; signal test fails | Gauge-to-scan comparison |
| Connector contamination or weak terminals | Oil intrusion/wiggle dropout | Terminal inspection |
| Reference, ground or signal fault | Loaded circuit test fails | Voltage-drop test |
| Wrong oil/filter or low level | Service history/level abnormal | Verify specification |
| Actual low engine oil pressure | Mechanical gauge below specification | Lubrication diagnosis |
A gauge protects the engine and diagnosis
It separates false sensor data from real lubrication loss.
Compare at specified temperature and rpm.
The revised sensor has a boundary
VIN/RRT status matters for 2013–2014 WK.
Do not extend it to every Grand Cherokee.
Connector oil can change signal
Inspect terminal grip and contamination.
Loaded tests reveal faults continuity misses.
Save these scan-data clues
Freeze frame is a snapshot of conditions when the PCM matured the fault. It can distinguish an idle-only problem from a load, cold-start or monitor-completion problem. Clearing first throws that context away.
- Exact VIN, platform, model year and engine sales code
- All confirmed, pending and permanent companion codes
- RPM, load, coolant temperature and vehicle speed
- Relevant commanded and actual scan data
- Recent service, repairs and symptom conditions
- Manufacturer bulletin and current software/VIN status
A practical diagnostic workflow
- 01Protect the engine
Stop for warning/noise.
- 02Check oil, filter and leaks
Verify exact parts and fill.
- 03Measure mechanical pressure
Use engine-specific temperature/rpm limits.
- 04Compare sensor and circuit
Load-test reference, ground and signal.
- 05Apply bulletin only if matched
Check year, platform and VIN.
- 06Verify hot and cold
Confirm pressure and no pending code.
Do not replace the most commonly named component from P0520 alone. Confirm the exact engine, preserve evidence and complete the manufacturer test sequence before ordering parts.
Why the model year changes the test
Grand Cherokee spans ZJ/WJ/WK/WK2/WL platforms and inline-six, V6, HEMI, diesel, turbo and 4xe powertrains. Oil-pressure control, EVAP hardware, cylinder banks, catalysts and cam sensors vary. Confirm platform, VIN, engine sales code, market and PCM calibration before using a bulletin or component diagram.
- The bulletin lists 2013–2014 WK.
- 3.6L, HEMI, diesel and later WL systems differ.
- P06DD adds a commanded oil-control question on applicable Pentastar engines.
- A red oil warning outranks the circuit code.
P0520 FAQ
Does P0520 mean pressure is low?+
Not necessarily, but pressure must be proven safe.
Can I drive?+
Not until safe mechanical pressure is established.
Can a connector cause it?+
Yes.
How is pressure confirmed?+
With the specified mechanical gauge.
Can P06DD appear too?+
Yes; it changes diagnosis toward pressure-control performance.
Should I use thicker oil?+
No.
Can the wrong filter matter?+
Yes, on engines whose oil control depends on the correct element and housing.
What confirms repair?+
Normal mechanical pressure, matching scan data and no pending code.
Ford diagnostic references
These documents explain Ford monitor operation. Exact pinpoint tests, connector views and specifications must be selected for the truck's VIN and model year in current service information.
01Chrysler Bulletin 18-034-14 Rev. A — P0520 revised sensorLists 2013–2014 WK Grand Cherokee and DS Ram 1500 among affected models; VIN/RRT verification applies↗02Stellantis/Mopar service informationFactory VIN-, platform-, engine-sales-code and calibration-specific service information↗03Mopar vehicle informationOfficial owner manuals and model-year engine, oil, warning and operating information↗