Jeep Wrangler P0520: Oil Pressure Switch/Sensor → Circuit

Common OBD2 trouble codes include P0520.  It’s generic, which means that it has the same meaning for the Jeep Wrangler as it would any other vehicle.  P0520 indicates that the oil pressure sensor is operating outside of its normal “range”.  This is usually caused by either a defective oil pressure sensor switch, or wiring problems.

Your Wrangler’s oil pressure sensor measures the oil pressure mechanically, and converts that reading into a voltage signal that the ECM (Computer) converts into an oil pressure reading.  This is the signal that triggers your oil warning light and appears on your oil pressure gauge.

Red oil alert lights are a sign of a problem.  Don't assume the oil pressure sensor has failed.  When there is no oil pressure, P0520 may occur.

The P0520 Quick Facts

• Most common is an oil pressure sensor.
• Low oil pressure can cause it.
• If you hear knocking or have the low oil pressure light, don’t drive until P0520 is diagnosed.
• Related to P0521.

P0520 Symptoms:  Jeep Wrangler

You may not notice any symptoms other than the check engine lights.  The oil pressure may be low if the engine is making unusual noises (e.g metallic or clacky). 

P0520 Causes:  Jeep Wrangler

• Oil Pressure Sensor Although the P0520 problem is most likely caused by the oil pressure sensor, it would still be wise to first check the oil quality and oil level, along with the wiring.
• Oil Pressure Sensor Wiring - If P0520 is displayed, it means that the oil pressure sensor signal has gone through a circuit problem.  It could be a problem with the wiring.
• Low oil consumption or none The first thing that you should do is check to see if there is oil in your vehicle’s engine at all.  It can also throw the P0520 code if it is low or empty.  This can be fixed by filling the oil with more, clearing the code and resetting the crankcase.  
• Low oil pressure The code will appear if oil pressure drops too low.  The oil light should indicate that it is present, as well as a reading of low oil pressure from the gauge. 
• Wrong oil or dirt? If your Wrangler’s oil hasn’t been changed for a long enough period of time, it can interfere with the oil pressure sensor, even if there still is oil pressure.

Wrangler P0520 Diagnosis

These are the steps that a mechanic will take to diagnose manually P0520 on your Jeep Wrangler.  

1. Take a look at the oil

First, check your oil level.  If it’s full make sure that it looks healthy.  The oil pressure sensor may be affected if the oil appears blackened or gritty.  If the vehicle is past it’s oil change deadline (regardless of how the oil looks), changing the oil would be a good idea.

2. Check the Wiring Harness

Next, you should inspect the wiring harness running from the oil pressure sensor to the ECM.  It could also be the cause of P0520.  Don’t forget to make sure that the harness is still plugged into the sending unit and undamaged.  

This code can be thrown for many reasons, including wiring issues.  The wiring is close to the Wrangler’s exhaust and can get brittle over time.

3. Manually check your oil pressure

If the wiring and oil levels are in good condition, you can manually test the oil pressure.  There are two options: Manual oil pressure gauge to see if it’s where it needs to be.  They're easy to use.  Here’s a Amazing YouTube video That will explain exactly how to use this gauge for checking.

If the oil pressure from the gauge reads ok, you’ll need to replace the oil pressure sending unit/sensor.  If there is low or no oil pressure, you’ll need to figure out why.

Conclusion:  P0520 Jeep Wrangler

The process of diagnosing P0520 can be done easily.  Check that the oil pressure has been checked if it is lit.  You will be successful in fixing your Wrangler.