The iconic Jeep Wrangler has always had a special place in the off-road enthusiast’s heart. However, even this tough and reliable beast can face some problems. One of them is the error code p0394.
If you are a proud Jeep Wrangler owner and come to face this issue, don’t worry, we’ve got you covered. By the end of this article, you will have no doubt about the Jeep Wrangler p0394 code and how to fix it.
What Does P0394 Jeep Wrangler Code Mean?
OBD2 trouble codes, or diagnostic trouble codes, are a car’s way of addressing its problem to you. When your Jeep Wrangler detects some error in the car, it will display a code to alert you about the problem.
The code p0394 means incorrect voltage readings from the camshaft sensor circuit B in engine bank 2. You might be clueless at this point and wondering about what that even means!
Actually, the camshaft sensor provides data about the camshaft spinning rate to the ECU to control the fuel and ignition of the engine. The camshaft reads the data through magnetic flux change and converts the information into voltage.
So, when the voltage data provided by the camshaft sensor does not match the PCM’s acceptable data set, it assumes that there is something wrong with the camshaft sensor circuit and informs you by showing code p0394.
The OBD2 code is divided into 4 parts. Let’s break down the trouble code p0394 displayed by your Jeep Wrangler:
- P: Powertrain, a total assembly of components that pushes a vehicle forward.
- 0: OBD2 standardized SAE code, known as generic code.
- 3: Vehicle ignition and engine misfire problems.
- 94: Specific reason for the error. Occasionally imprecise voltage readings from the camshaft sensor circuit B in engine bank 2 in this case.
P0394 Code: What Causes Camshaft Sensor Circuit Problem on Jeep Wrangler?
The camshaft and camshaft position sensor consists of numerous parts that are responsible for sending wrong data to the engine control module and showing the p0394 trouble code. Here are some possible causes for the Jeep Wrangler p0394 error code:
- Oil or engine fluid leaks
- Camshaft position sensor that is open or shorted
- The camshaft position sensor circuit with a bad electrical connection.
- Electrical components such as wires and connections that are shorted, grounded, loose, or malfunctioning
- Camshaft position sensor failure
- In rare situations, PCM failure
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How to Troubleshoot & Fix P0394 Jeep Wrangler Code?
Trying to fix the Jeep Wrangler p0394 error can be frustrating and confusing because there are many possible causes. Don’t panic, with our detailed step-by-step troubleshooting guide and clear explanations, it wouldn’t be hard to tackle.
Take your time and go through each step carefully so that you don’t miss any critical points. And by the end of this troubleshooting session, you will have your Jeep Wrangler’s p0394 code fixed.
Step 01: Check the Engine Oil
You may wonder at first what engine oil has to do with a camshaft position sensor. But you should note that when engine oil is too low, it can overheat the engine and surrounding components. For that reason, the camshaft position sensor will not work properly due to overheating.
Also, the same situation can occur due to low oil pressure, contaminated or deteriorated engine oil, incorrect oil viscosity, or even an incorrect engine oil filter. If any of these oil issues are present in your Jeep Wrangler, solve them.
Add proper engine oil to the acceptable limit and keep the engine idle for 3-4 minutes after starting it. Then turn the engine off with the ignition on and erase the p0394 error code using a diagnostic tool. After that, start the Jeep Wrangler and drive to see if the code appears again. If the code persists, go to step 2.
Read Also: How to Troubleshoot and Fix P0507 Jeep Commander DTC Code?
Step 02: Check Power Supply Circuit to Camshaft Position Sensor
Make sure that your battery is connected and the ignition is turned on before this step. Here we will check if the sensors are receiving power by checking the voltage. Because without a proper power supply through the circuit, the camshaft sensor won’t work properly.
First, disconnect the camshaft position sensor 2 (engine bank 2) from the harness connector. Observe the pins labeled 1, 2, 3, and 4 on the underside of the sensor plug. Using a multimeter, check for five volts on pins 1, 2, and 4, and ground on pin 3.
- Wiggle the wire while inspecting the pins to ensure there is no interruption.
- Examine the ground and the meter for a green light.
If you see there is a loose connection or the voltage fluctuates, fix that. There can be an open or short circuit on the harness wiring, which was causing problems with the sensor data. After repairing the circuit problems, your error code should be gone by now.
Step 03: Checking for Faulty Camshaft Position Sensor
If your Jeep Wrangler cleared the first two procedures, the only likely suspect is the camshaft sensor itself. Don’t rush before buying a new sensor, we still need to ensure that the sensor is faulty.
- Disconnect the connectors for both bank 1 and 2 camshaft position sensors,
- Remove the camshaft position sensor from bank 1 and replace it with bank 2’s place.
- Perform the Cam Relearn procedure using a diagnostic tool else it might result in a misfire.
- Reconnect the camshaft position sensor and powertrain control module connectors.
- After only turning the ignition, erase the error p03994 from your jeep wrangler using a diagnostic or scan tool.
- Start the engine and try to operate the Jeep Wrangler similar to freeze frame data and check the error code.
Now check the error code. If the error code is replaced with p0340 or it shows any error code for the opposite bank camshaft, it indicates that there is a problem with your camshaft sensor, and you need to replace it.
Step 04: PCM Test
If any of the above were not the cause, then there might be a problem with the PCM that is causing the fake error code. PCM-related problems are not new to the Jeep Wrangler. It is the 5th most common problem with Jeep Wranglers, with 1691 cases on the carproblemzoo website.
First, disconnect all connectors, including PCM and component harness connectors. Then Check all connectors, terminals, and seals for damage, corrosion, water intrusion, or other issues. Repair if you find any issues in there.
After that, reconnect all connectors securely. Finally, use a scan tool to check for the P0019 code. If you see error code p0019, you may need to replace the PCM (Powertrain Control Module) and after reprogramming the PCM, performing a Powertrain Verification test is necessary.
A new PCM might cost around 650$ and the total replacement cost can go up to 750$ considering the labor and other costs.
Read Also: How to Troubleshoot & Fix P0507 Jeep Grand Cherokee Code?
What if any of these didn’t work?
If your PCM turns out to be working fine in Step 4, then there might be other hidden, serious issues with your Jeep Wrangler. In that case, you should take your car to the dealership for their support.
Now that you have a clear idea about Jeep Wrangler error code p0394 and how you can fix it, here are answers to FAQs to clear your further doubts!
Can you drive a Jeep Wrangler with P0394 Code?
No, you shouldn’t drive your Jeep Wrangler if it has a camshaft sensor circuit issue. It can be risky for you and your car, and you should take immediate action as soon as you see a problem.
How much does it cost to fix Jeep Wrangler P0394 code?
A new replacement camshaft position sensor for a Jeep Wrangler might cost you around $50 for parts and around $100 for labor. Although the exact price can vary depending on your model and repair location.
What happens if a Jeep Wrangler camshaft sensor fails?
When a camshaft position sensor fails, the ECM turns off the fuel and spark supplies. If you ignore the indicators that your camshaft position sensor is failing, your Jeep Wrangler engine will ultimately fail to start.
Even the finest vehicles like the Jeep Wrangler can face camshaft sensor issues, although the reported cases are only a few on sites like Carproblemzone. Hence, you shouldn’t ignore the p0394 error code and should address it as soon as you see it! Early repairs always save from future expensive repair loads.