P2459 – DPF Pressure Sensor A Circuit Current High

In the world of diesel engines, the diesel particulate filter (DPF) plays a crucial role in reducing harmful emissions. However, when the DPF pressure sensor malfunctions, it can lead to issues such as high circuit current. This troublesome situation is indicated by the P2459 trouble code, which is stored by the engine control module (ECM) when the voltage from the DPF regeneration system exceeds the manufacturer’s specified parameters.

When faced with the P2459 code, it is important to diagnose the root cause and take appropriate actions to rectify the issue. Some of the common culprits behind this code include a faulty DPF pressure sensor, malfunctioning exhaust pressure sensor, insufficient diesel exhaust fluid, problems with the diesel exhaust fluid, and wiring issues in the DPF injection system.

Key Takeaways:

• P2459 indicates a high circuit current in the DPF pressure sensor.
• Common causes include faulty DPF pressure sensor, issues with the exhaust pressure sensor, and problems with the diesel exhaust fluid.
• Potential repairs include replacing or repairing various components such as the DPF pressure sensor, diesel exhaust fluid heater, and engine control module.
• Symptoms of the P2459 code may include an illuminated check engine light, black smoke from the exhaust, and overheating of DPF housing or exhaust components.
• Diagnostic tools such as an OBD-II scanner and digital volt/ohmmeter are essential for accurate diagnosis and repair.

Symptoms of P2459 Code

The symptoms of the P2459 code may include an illuminated check engine light, black smoke coming from the exhaust, other accompanying DPF codes, inability to maintain RPMs, rise in engine temperature, or overheated DPF housing or exhaust components.

It is important to pay attention to these symptoms as they can indicate a malfunction in the diesel particulate filter (DPF) pressure sensor or other related components.

Common Causes

The common causes for the P2459 code include:

• Malfunctioning DPF pressure sensor
• Restricted DPF or exhaust system
• Accumulated soot within the DPF
• Electrical circuit problems
• Faulty fuel system
• Damage to the diesel oxidation catalyst (DOC) or DPF filter
• Air leaks
• Bad fuel filters
• PCM-related concerns

These common causes should be thoroughly investigated during the diagnostic process to pinpoint the exact issue contributing to the P2459 code.

How to Correct P2459 Code

When it comes to addressing the P2459 code, the specific repairs needed will depend on the diagnosis. However, there are some common troubleshooting steps and repair options to consider:

1. Repair the Faulty DPF Pressure Sensor: If the DPF pressure sensor is found to be faulty, it should be repaired or replaced. This sensor plays a crucial role in monitoring the pressure within the diesel particulate filter.
2. Fill the Diesel Exhaust Fluid: Ensuring sufficient diesel exhaust fluid is present is important for the proper functioning of the DPF system. If the fluid level is low, it should be topped up.
3. Adjust Wiring Faults in the DPF Injection System: Check for any wiring faults or loose connections in the DPF injection system. Adjust or repair the wiring as necessary.
4. Recondition the Non-Functioning Exhaust Pressure Sensor: If the exhaust pressure sensor is malfunctioning, it may need to be reconditioned or replaced. This sensor helps monitor the pressure levels in the exhaust system.
5. Address Flawed PCM or PCM Programming Errors: If there are any flaws or errors in the powertrain control module (PCM) or its programming, they should be addressed. Sometimes, reprogramming the PCM may be necessary to rectify the issue.
6. Inspect and Repair Other Components: Depending on the diagnosis, it may be necessary to inspect and repair other components related to the DPF system. These can include the diesel exhaust fluid heater, engine control module, diesel exhaust fluid pump, diesel particulate filter, exhaust gas recirculation valve, fuel injector, fuel tank pressure sensor, or electronic control unit.

By following these troubleshooting steps and making the necessary repairs, you can effectively correct the P2459 code and ensure the proper functioning of your diesel engine.

If you require assistance or encounter difficulties during the repair process, it is recommended to seek help from a qualified mechanic with experience in diagnosing and repairing issues related to the P2459 code.

Easy Diagnosis of P2459 Code

Diagnosing the P2459 code requires the use of diagnostic tools and a specific diagnostic procedure. By following these steps, you can identify the underlying issues causing the code and take appropriate actions for repair.

Diagnostic Tools

For diagnosing the P2459 code, you will need the following diagnostic tools:

• A scanner: Used to connect to the vehicle’s diagnostic port and retrieve trouble codes and freeze frame data.
• Digital volt/ohmmeter: Helps test the battery, alternator, and check system-related wiring harnesses and connectors.
• Vehicle service manual: Provides detailed information about the specific diagnostic procedure for your vehicle.

Diagnostic Procedure

Follow these steps to diagnose the P2459 code:

1. Connect the scanner: Connect the scanner to the vehicle’s diagnostic port.
2. Retrieve trouble codes and freeze frame data: Use the scanner to retrieve the trouble codes and freeze frame data associated with the P2459 code.
3. Inspect system-related wiring harnesses and connectors: Check all system-related wiring harnesses and connectors for any damage or loose connections. Repair or replace as necessary.
4. Test the battery and alternator: Use the digital volt/ohmmeter to test the battery and alternator to ensure they are functioning properly.
5. Check diesel exhaust fluid level and quality: Verify the level and quality of the diesel exhaust fluid. Insufficient or contaminated fluid can lead to code P2459.
6. Perform DPF regeneration system activation: Activate the diesel particulate filter (DPF) regeneration system to test its functionality. Follow the instructions in the vehicle service manual.
7. Replace the DPF pressure sensor (if necessary): If the DPF pressure sensor is found to be faulty or not complying with manufacturer specifications, replace it with a new one.

By following this diagnostic procedure and using the necessary tools, you can accurately diagnose the P2459 code and identify the specific issues that need to be addressed for repair.

Proper diagnosis is crucial to efficiently address the P2459 code. Using diagnostic tools such as a scanner and digital volt/ohmmeter, you can retrieve trouble codes, inspect wiring, and test components to pinpoint the cause of the code. Following the diagnostic procedure outlined above ensures a systematic approach to diagnosis, helping you identify and resolve the issues with confidence.

Common Mistakes When Diagnosing P2459 Code

When dealing with the P2459 code, it is crucial to avoid common mistakes that can hinder the diagnosis process and lead to ineffective repairs. By understanding these mistakes and taking proactive measures, you can save time and effort in resolving the issue.

• Overlooking flaws in the diesel particulate filter (DPF): The DPF plays a critical role in filtering harmful emissions from the exhaust system. Neglecting to inspect the DPF for any damage or clogging can prevent proper diagnosis and resolution of the P2459 code.
• Failing to complete a manual regeneration: Conducting a manual regeneration on the DPF helps to burn off accumulated soot and cleanse the filter. Skipping this step can result in inaccurate diagnosis and ineffective repairs.
• Not checking for other diagnostic codes related to the DPF pressure sensor: The P2459 code may not be the only code related to the DPF pressure sensor. It is important to scan for additional codes to ensure a comprehensive diagnosis and avoid overlooking underlying issues.

Thoroughly diagnosing and repairing any issues with the DPF pressure sensor before attempting to address the P2459 code is crucial. Additionally, it is worth noting that the DPF pressure sensor hoses/lines are prone to clogging and collapse, which can impact the sensor’s functionality. Furthermore, using incorrect or insufficient diesel exhaust fluid can lead to DPF regeneration failure and should be avoided.

Diagnostic Tools and Estimated Repair Cost

To accurately diagnose and address the P2459 code, you will need several diagnostic tools at your disposal. These essential tools include an OBD-II scanner, a digital multimeter, and, depending on the situation, a DPF cleaning kit. With these tools, you can effectively identify the underlying issue causing the code and proceed with the appropriate repairs.

When it comes to the estimated repair cost for resolving the P2459 code, it’s important to note that the total expense can vary based on the specific repairs required. On average, the repair costs for this code can range from $50 to $500. The ultimate cost will depend on several factors, such as the replacement of the DPF pressure sensor, inspecting and repairing the exhaust system, professional DPF cleaning service, replacing the diesel oxidation catalyst (DOC) or DPF filter, and updating or replacing the powertrain control module (PCM).

As you can see, the estimated repair costs are primarily influenced by the specific components that need attention. To gain a better understanding of the potential repair expenses, it’s recommended to consult with a reputable mechanic or utilize an online resource that provides pricing information for automotive repairs.

Conclusion

Understanding and addressing the P2459 code is essential for maintaining the optimal performance of your diesel engine. By following the proper diagnostic procedure and utilizing the necessary tools, you can effectively troubleshoot and repair issues related to the DPF pressure sensor and high circuit current. Whether it requires replacing faulty components, adjusting wiring faults, or performing cleaning or regeneration processes, resolving the P2459 code will help ensure the efficient operation of your diesel engine, minimizing emissions, and promoting a healthier environment.

However, it’s important to note that troubleshooting and repairing the P2459 code can be complex and challenging. If you are unsure or encounter difficulties during the repair process, it is highly recommended to seek assistance from a qualified mechanic. A professional mechanic will have the expertise and knowledge to properly diagnose and resolve the issue, ensuring that the repair is done correctly and safely.

In summary, the P2459 code related to the DPF pressure sensor and high circuit current is a common problem in diesel engines. By taking the necessary steps to troubleshoot and repair the issue, you can maintain the optimal performance of your diesel engine, reduce emissions, and ensure the longevity of your vehicle.