The P2059 trouble code is a diagnostic trouble code (DTC) that indicates an issue with the reductant injection air pump control circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which is used in vehicles manufactured since 1996. The P2059 code specifically points to an open circuit condition in the reductant injection air pump control circuit, which is crucial for the operation of selective catalytic reduction (SCR) systems in diesel engines. Understanding this code is essential for vehicle owners and DIY mechanics, as it can significantly impact vehicle performance and emissions.
| P2059 Code Meaning | P2059 Code Common Causes |
|---|---|
| Reductant Injection Air Pump Control Circuit/Open | Defective reductant air pressure sensor |
| Indicates a malfunction in the SCR system | Faulty reductant injection air pump |
| Potential catalyst damage if not addressed | Open or shorted circuits in the control circuit |
| May illuminate the check engine light (MIL) | Bad SCR controller or PCM issues |
Symptoms of P2059 Code
When the P2059 code is triggered, several symptoms may manifest, indicating that there is a problem with the reductant injection system:
- Reduction in Fuel Efficiency: A malfunctioning SCR system can lead to increased fuel consumption as the engine struggles to operate efficiently.
- Excessive Black Smoke: The vehicle may emit more black smoke from the exhaust due to incomplete combustion processes.
- Diminished Engine Performance: Drivers may notice a lack of power or responsiveness from the engine.
- Illumination of Check Engine Light: The malfunction indicator lamp (MIL) may light up on the dashboard, alerting the driver to a potential issue.
Technical Explanation of P2059 Code
The P2059 trouble code relates to the reductant injection air pump, which plays a vital role in SCR systems designed to reduce nitrogen oxide (NOx) emissions in diesel engines. This system uses diesel exhaust fluid (DEF), which is injected into the exhaust stream to facilitate chemical reactions that convert harmful pollutants into harmless nitrogen and water.
The powertrain control module (PCM) monitors various sensors and circuits within this system. If it detects an open circuit in the reductant injection air pump control circuit, it triggers the P2059 code. This condition could be caused by several factors, including wiring issues, faulty components, or problems with the PCM itself.
Step-by-Step Diagnosis of P2059 Code
Diagnosing a P2059 trouble code involves several systematic steps:
- Check for Additional Codes: Use an OBD-II scanner to check if other trouble codes are present. Address any additional codes first.
- Visual Inspection: Inspect wiring and connectors associated with the reductant injection air pump for signs of damage, corrosion, or loose connections.
- Test Reductant Air Pressure: Ensure that the reductant supply system is maintaining proper pressure. Activate the pump and check for leaks.
- Use a Digital Volt/Ohmmeter (DVOM): Measure voltage and resistance in the control circuit. Disconnect components as necessary for accurate readings.
- Inspect Components: Check the functionality of the reductant injection air pump and associated sensors. Replace any defective components found during testing.
- Consult Technical Service Bulletins (TSBs): Refer to manufacturer-specific TSBs for additional diagnostic guidance related to your vehicle make and model.
- Clear Codes and Test Drive: After repairs are made, clear any stored codes and take the vehicle for a test drive to see if the P2059 code reappears.
Solution Methods for P2059 Code
Addressing a P2059 trouble code typically involves repairing or replacing faulty components within the reductant injection system:
- Repair or Replace Wiring: If damaged wiring or connectors are found during inspection, they should be repaired or replaced to restore proper electrical flow.
- Replace Defective Components: If tests indicate that the reductant injection air pump or pressure sensor is faulty, these parts should be replaced.
- Check Powertrain Control Module (PCM): In some cases, issues with programming or failure of the PCM itself may require reprogramming or replacement.
- System Reset: After repairs are completed, reset all codes using an OBD-II scanner and ensure that all systems are functioning correctly during a test drive.
Cost Estimates
The cost of diagnosing and repairing a P2059 trouble code can vary significantly based on several factors:
- Diagnostic Fees: Expect to pay between $100-$150 for a professional diagnostic service at an auto repair shop.
- Parts Replacement Costs:
- Reductant Injection Air Pump: $200-$600
- Reductant Pressure Sensor: $50-$150
- Wiring Harness Repair: $50-$200 depending on extent of damage
- Labor Costs: Labor rates can vary from $75-$150 per hour depending on location and shop rates.
Overall, total repair costs can range from $300 to over $1,000 depending on what needs to be fixed.
Warnings and Recommendations
- Professional Help Recommended: If you are not experienced with automotive diagnostics and repairs, it is advisable to seek help from a qualified mechanic to avoid further complications.
- Timely Repairs Needed: Ignoring a P2059 trouble code can lead to more severe engine issues and potential damage to emissions components, which can be costly to repair.
- Regular Maintenance: Ensure regular maintenance checks on your vehicle’s emission systems to prevent issues before they arise.
Frequently Asked Questions About P2059
- What does error code P2059 mean?
P2059 indicates an open circuit in the reductant injection air pump control circuit, affecting your vehicle’s SCR system. - How serious is a P2059 code?
This code should be considered serious as it can lead to catalyst damage and increased emissions if not addressed promptly. - Can I drive my car with a P2059 code?
While you can technically drive with this code present, it is not recommended due to potential performance issues and emissions violations. - What vehicles are affected by P2059?
P2059 applies to many OBD-II vehicles from manufacturers like Dodge, Ford, Mercedes-Benz, Audi, and Volkswagen. - What are common symptoms of a P2059 code?
Symptoms include reduced fuel efficiency, excessive black smoke from exhaust, diminished engine performance, and illuminated check engine light. - How much does it cost to fix a P2059 code?
The cost can range from $300 to over $1,000 depending on parts needed and labor costs. - Can I fix a P2059 code myself?
If you have automotive repair experience and access to diagnostic tools, you may be able to fix this issue yourself; otherwise, consult a professional. - What should I do if my vehicle shows a P2059 code?
Perform diagnostics as outlined above or take your vehicle to a trusted mechanic for assessment and repair.
In conclusion, understanding and addressing the P2059 trouble code is crucial for maintaining optimal vehicle performance and compliance with emission standards. By following systematic diagnosis steps and knowing when professional help is needed, vehicle owners can effectively manage this issue. Regular maintenance checks can also help prevent such problems from arising in the future.