Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that there's a problem with the part of the car that controls how a special fluid is sprayed into the exhaust to make it cleaner. It's like a squirt gun not working right.
The P201A code indicates an issue with the electrical circuit that controls the reductant injection valve in the exhaust system, specifically on bank 2, unit 1.
The reductant injection valve is part of the Selective Catalytic Reduction (SCR) system, which injects diesel exhaust fluid (DEF) into the exhaust stream to reduce NOx emissions. The P201A code is triggered when the Engine Control Module (ECM) detects a performance issue or an out-of-range condition in the circuit controlling this valve.
• Check Engine Light is on
• Reduced engine performance
• Increased emissions
• Faulty reductant injection valve
• Wiring issues in the circuit
• Defective ECM
Reductant: A substance used to reduce emissions, often diesel exhaust fluid in diesel engines.
SCR: Selective Catalytic Reduction, a system used to reduce 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.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect and maintain the exhaust system.
• Use high-quality diesel exhaust fluid.
• Ensure all electrical connections are secure.
Emission Control System Issue
• Avoid driving long distances until repaired.
• Have the vehicle inspected by a professional mechanic.
Check with the vehicle manufacturer for emission system warranty coverage.
This code has become more common with the increased use of SCR systems in diesel engines to meet stricter emission standards.
Moderate – While the vehicle may still be drivable, it should be repaired soon to avoid increased emissions and potential engine performance issues.
Driving with a malfunctioning emission control system may violate emissions regulations and contribute to air pollution.
• Engine running
• Vehicle at normal operating temperature
The reductant injection valve is typically located near the exhaust system, on the side of the engine corresponding to bank 2.
Q: Can I drive with a P201A code?
A: It's possible to drive short distances, but it's best to get it fixed soon to avoid further issues.
Q: What happens if I ignore the P201A code?
A: Ignoring the code can lead to increased emissions and potential damage to the exhaust system.
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