P0325 Code – Meaning, Causes, Symptoms (& How To Fix)

When the Check Engine Light comes on your dashboard, it’s important to whip out your code scanner to see what’s going on. The steps you need to resolve the issue quickly if the P0325 code is received can be found here.

Not only do we cover the meaning of the P0325 trouble code, but we show you what symptoms you may notice when it’s going on. You can also find out the most common causes.

Definition of Code P0325

P0325 – Knock Sensor Circuit Malfunction (Sensor 1, Bank 1)

What is the P0325 Codification?

The P0325 DTC states that there’s a Knock Sensor Circuit Malfunction (Sensor 1, Bank 1). Powertrain Control Module (PCM), detected an issue with either the circuit or knock sensor. This is the Bank 1 sensor that's located on the opposite side to the motor from the #1 cylinder.

The engine’s knock sensor is meant to detect abnormal vibrations occurring because of trouble with the combustion. Some cars may have more than one of these sensors. If the PCM notices that the signal goes beyond predetermined specifications, the trouble code will be issued. 

READ MORE: Bank 1 vs Bank 2 – Sensor 1 & 2 (Locate O2 Sensors)

Trouble code P0325 Symptoms

One certainty with the P0325 code: The Check Engine Light will turn on. Beyond that, it’s possible to notice a few other symptoms, mainly dealing with the drivability and performance of the vehicle.

These are some of the most common symptoms associated with P0325 DTC.

What is the P0325 Code?

Because this code has to do with the knock sensor, you are going to automatically assume that’s the part that has failed. While this might be the case, it’s important to walk through all of the diagnostic steps to be sure.

These are some of the most popular P0325 DTC causes.

• Defective knock sensor
• Broken or defective wiring
• Failure of PCM is not as probable

RELATED: 5 Symptoms of a Bad Knock Sensor (& Replacement Cost)

What is the P0325 code?

Low – For the most part, there’s no reason to run to the auto repair shop due to this code. It should not be a problem to drive your car wherever you want it to without any other damages.

There could also be an issue with driving ability due to a loss of power. Without the sensor working as it should, it also becomes more difficult to know if something goes wrong with the combustion process, so you don’t want to put off the repair if you can help it. 

How can you fix the P0325 code?

You don’t need to wonder how to fix the P0325 trouble code. With the proper diagnostic steps, it’s easy to pinpoint the exact problem, so you ensure the issue gets resolved the right way. You might discover that you are in need of one of the repairs after you have gone through all the steps.

• Replacing the knock sensor
• Reconnect a bad connection, or fix faulty wiring
• Replace/update PCM 

Common mistakes in diagnosing P0325

This trouble code P0325 seems to be a strong indicator that your knock sensor may not be in good condition. However, you can’t just make assumptions without taking the time to verify the problem.

It is possible to miss something important if you ignore the diagnosis and inspection. In the end, you could replace parts that aren’t needed, thereby wasting your time and money. 

How to diagnose P0325 Trouble code

Even if you aren’t a professional mechanic, you can use your code scanner to get to the bottom of the P0325 code. Here are a few steps to consider trying, but you should also reference your car’s service manual for more instructions.

1. Make sure to check the engine codes. Notify any codes you see.
2. To find out what the code is, clear it and run a road test.
3. You can use the live data function of your scanner to measure the voltage at the knock sensor and ensure that it is within the service manual's range.
4. The wiring and connections of the knock detector should be examined. This is especially important if you don’t get any signal from your previous step. To eliminate the code, fix any broken or missing wires first.
5. If you still get the same code, replace the knock sensor or harness.

If these steps haven’t resolved your issues, it’s best to visit your local auto repair shop. The PCM must be examined by professionals. 

Projected Repair Costs of P0325

You should be able to use the above-mentioned diagnostics steps to find the correct repair. But you want to understand what your budget is. Here are some top repair options, as well the estimated labor and parts cost. 

• Replace knock sensor – $275-$425
• Repair damaged connection or malfunctioning wiring – $50-$450
• Updates/replace PCM – $250-$2,500

The P0325 Code: Mechanics Tips

Your scan tool quality is very important when dealing with P0325. While there are plenty of cheap scan tools that will get you the codes, many of them don’t have the additional features that help you with the diagnostics.

To diagnose this DTC more accurately, invest in an OBD-II scanner tool. With the live data stream, you can get to the bottom of what’s going on much quicker than if you have the basic functions only.