Chrysler-made vehicles, such as the Jeep Cherokee, commonly use an oil pump with a high-pressure mode and a low-pressure mode. P06DD is stored in the PCM’s (powertrain control module) memory when the engine is stuck in low-pressure mode.
P06DD is a very common code to find in the Cherokee. P06DD can be caused by a failure in the dual-stage oil pump, More often than not, clearing this code will not involve dealing with the oil pump.
P06DD Definition: Dual Stage Oil Pump – Stuck Low
The definition of Chrysler P06DD consists of two parts. The first part is the part of the vehicle that is having the issue, and the second is what that issue is.
Dual Stage Oil Pump
Your Jeep Cherokee uses a dual-stage oil pump. The design uses seven vanes and a moving element to regulate oil pressure and keep it at a near-constant level. It can run in low or high-pressure mode depending on the engine’s needs.
- Low-Pressure Mode– This mode is activated when the control solenoid is on. It keeps your Cherokee’s oil pressure around 29 psi and is active from idle to around 3000 RPM.
- High-Pressure Mode– High-pressure mode is activated somewhere between 3000-4000 RPM and keeps the engine’s oil pressure around 65 psi. It can kick in earlier if the oil and coolant temperatures are low.
Maximum oil pressure is limited to 145 psi by a relief valve and monitored by the Engine Oil Pressure (EOP) sensor.
The engine goes into low-pressure mode when the oil pressure control solenoid is switched on.
Stuck Low
The dual-stage oil pump is stuck in the low-pressure mode described above, which means the engine may not be getting enough oil pressure above 3k RPM.
Jeep Cherokee P06DD: Symptoms
Assuming there are no other codes, the only symptom you should notice with P06DD is the check engine light.
Jeep Cherokee P06DD: Causes & Diagnosis
Below, we’ve listed some of the most common problems that can cause P06DD in the Jeep Cherokee. It’s not often caused by a bad oil pump (a common misdiagnosis).
Check TSB’s
The first thing you need to do is check to see if there are any technical service bulletins for your model year Cherokee. Some years (particularly before 2017) require an ECM reflash to fix this problem.
There are plenty of TSB sites where you can look these up.
Oil Problems
If the engine oil is too low, your Cherokee’s dual pressure pump can’t increase oil pressure past the low-pressure range. The first thing you should do if you have P06DD is check the oil. Dirty oil can cause P06DD. Any oil that has lost its viscosity can cause this code.
Wrong Oil Filter
Penstar engines will often get P06DD when the wrong type of oil filter was used. If you’ve recently had your oil changed and the check engine light came on, this is a very likely cause.
When replacing your Cherokee’s oil filter, verify the oil pressure bypass valve is intact. A missing bypass valve is a less likely cause, but as long as you’re down there anyway, you might as well check.
Change the oil filter to the MOPAR Oil filter recommended in the owner’s manual. This is a very common fix for P06DD.
Oil Pressure Sensor
The oil pressure sensor is one of the most common fixes for P06DD. Here’s a video on diagnosing and replacing one on a Chrysler 3.6L engine.
The oil pressure sensor could have a wiring issue (short or open). But, it takes a decent amount of digging to get to the harness. As you can see in the video above, you must pull a lot of the engine apart to get to it.
Mechanical Issue
Here are some of the common mechanical issues that can cause P06DD in the Jeep Cherokee:
- Bad/Missing oil bypass valve
- Bad dual-stage oil pump
- Use of an oil filter adapter
Conclusion
P06DD in the Jeep Cherokee can be a challenge to diagnose. But, there many of the common fixes are super easy to check. Good luck!