Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of your car that helps reduce pollution. It's like a special spray bottle that helps clean the air coming out of your car, and it's not working right.
The reductant injection valve is part of the Selective Catalytic Reduction (SCR) system, which reduces harmful emissions by injecting a urea-based fluid into the exhaust. This code indicates that the electrical circuit for this valve is showing a high voltage condition.
The P2055 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the reductant injection valve circuit for Bank 1 Unit 2. This can be due to a short circuit, open circuit, or a faulty valve. The SCR system relies on precise control of the reductant injection to reduce NOx emissions effectively.
• Check Engine Light is on
• Increased exhaust emissions
• Possible reduction in engine performance
• Faulty reductant injection valve
• Open or shorted wiring in the valve circuit
• Poor electrical connection in the valve circuit
Reductant: A substance used in the SCR system to reduce emissions.
SCR: Selective Catalytic Reduction, a system that reduces NOx emissions in diesel engines.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant injection valve for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant injection valve if faulty.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly inspect and maintain the exhaust system.
• Use high-quality diesel exhaust fluid (DEF).
• Keep electrical connections clean and secure.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving with this issue for extended periods.
Check with your vehicle manufacturer for emissions-related warranty coverage.
This code has become more common with the increased use of SCR systems in diesel vehicles to meet stricter emission standards.
Moderate – Address the issue soon to avoid increased emissions and potential engine performance issues.
Operating a vehicle with a malfunctioning emissions system may violate emissions regulations and contribute to environmental pollution.
• Engine running
• Vehicle at operating temperature
The reductant injection valve is typically located near the exhaust system, close to the SCR catalyst.
Q: Can I drive with a P2055 code?
A: It's possible to drive, but it's not recommended as it may increase emissions and potentially affect engine performance.
Q: What is a reductant injection valve?
A: It's a component in the SCR system that injects a urea-based fluid into the exhaust to reduce emissions.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.