P0520 is an oil-pressure sensor circuit plausibility fault, but a code cannot prove the engine has safe oil pressure. Check level and leakage, then install the specified mechanical gauge when warning/data/noise is concerning. Compare actual pressure with scan data while testing 5-volt reference, ground, signal, connector contamination and harness. Chrysler bulletin 18-034-14 Rev. A lists 2013–2014 JK Wrangler among vehicles for a revised oil-pressure sensor, with VIN/RRT verification. It does not cover every Pentastar year or replace the need to prove pressure.
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 before electrical-only diagnosis.
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 |
|---|---|---|
| Failed oil-pressure sensor | Mechanical pressure normal; signal/circuit test fails | Gauge-to-scan comparison |
| 2013–2014 revised-sensor branch | Exact JK/VIN/RRT applicability | Bulletin check |
| Connector contamination/terminal fault | Oil intrusion or wiggle dropout | Terminal inspection and loaded test |
| Reference/ground/signal wiring fault | Voltage or continuity under load fails | Circuit test |
| Actual low oil pressure | Mechanical gauge below engine specification | Lubrication-system diagnosis |
Circuit code and lubrication safety coexist
A failed sensor can falsely report pressure, but a real pump/bearing/filter problem can also create implausible data.
The safe order is physical level/leak check, mechanical pressure, then electronics.
The revised sensor branch is bounded
Chrysler lists specific 2013–2014 models and requires VIN/RRT lookup.
A later Wrangler with the same code needs its own part and diagnostic path.
Compare pressures at defined conditions
Oil temperature and rpm change pressure substantially.
Record both so a hot-idle value is not compared with a cold fast-idle specification.
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.
- Oil level/grade/filter and leakage
- Oil warning/noise
- Scan pressure versus mechanical gauge
- P0522/P0523/P06DD companions
- 5V reference/ground/signal
- VIN/year/engine and bulletin status
A practical diagnostic workflow
- 01Protect engine
Shut down for warning/noise or unverified zero pressure.
- 02Check oil/filter/leaks
Correct gross problems without assuming the sensor.
- 03Measure mechanical pressure
Use the engine-specific port/spec at temperature/rpm.
- 04Compare sensor and circuit
Test loaded reference, ground and signal.
- 05Check 2013–2014 bulletin
Verify VIN/RRT before revised sensor repair.
- 06Confirm hot and cold
Verify pressure/data and no pending code.
Do not replace the sensor before proving mechanical pressure if there is a warning or noise. Do not assume bulletin 18-034-14 covers a 2012 or 2015 Wrangler, and never install thicker oil to hide pressure loss.
Why the model year changes the test
Wrangler spans YJ/TJ 2.5L and 4.0L engines, JK 3.8L and 3.6L Pentastar, JL 2.0L turbo, upgraded 3.6L, 4xe hybrid, 3.0L diesel and 6.4L applications. Oil systems, cylinder banks, cam sensors, EVAP leak detection and catalyst layouts differ. Confirm platform (TJ/JK/JL), VIN, model year, engine/sales code, market and PCM software level before applying a bulletin or parts recommendation.
- 18-034-14 lists 2013–2014 JK Wrangler.
- P0520 is circuit plausibility; P06DD addresses dual-stage pressure-control performance on applicable engines.
- 3.8L, 3.6L, 2.0T, diesel and 4xe systems have different pressure hardware/specs.
- Oil-filter/housing service history matters on Pentastar engines.
P0520 FAQ
Does P0520 mean oil pressure is low?+
Not necessarily, but pressure must be verified when warnings/noise exist.
Can I drive?+
Not until safe pressure is established.
Does the bulletin cover every JK?+
No; it lists 2013–2014 and requires VIN/RRT verification.
Can a connector cause it?+
Yes, through oil contamination, loose terminals or wiring damage.
How is pressure confirmed?+
With the specified mechanical gauge and engine-specific limits.
Can P06DD appear too?+
Yes; it changes diagnosis toward pressure-control performance.
Should I use thicker oil?+
No; use the specified oil and diagnose the cause.
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 Service Bulletin 18-034-14 Rev. A — Wrangler P05202013–2014 JK among listed models; revised engine-oil-pressure sensor branch and VIN/RRT verification↗02Mopar vehicle information and owner manualsOfficial Wrangler operating, warning, engine-oil and model-year identification information↗03Stellantis/Mopar service informationFactory service, recall and vehicle information access; use VIN and engine sales code↗