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 the car's computer is getting a signal that the sensor checking the quality of a special fluid used to clean the exhaust is reading too high. It's like when a thermometer shows a temperature that's too high.
The P206D code is triggered when the Engine Control Module (ECM) detects a high voltage signal from the reductant quality sensor circuit.
The reductant quality sensor is part of the vehicle's selective catalytic reduction (SCR) system, which helps reduce emissions. This sensor measures the quality of the diesel exhaust fluid (DEF) to ensure it meets the required standards for efficient operation. A 'circuit high' condition indicates that the sensor is sending a higher than expected voltage signal to the ECM, which could mean an issue with the sensor, wiring, or the fluid itself.
• Check Engine Light illuminated
• Possible reduction in engine performance
• Increased emissions
• Faulty reductant quality sensor
• Wiring issues such as shorts or open circuits
• Contaminated or incorrect diesel exhaust fluid (DEF)
Reductant: A substance used to reduce emissions in the exhaust system.
SCR: Selective Catalytic Reduction, a system used to reduce nitrogen oxide emissions in diesel engines.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the reductant quality sensor for damage.
• Test the reductant quality sensor with a multimeter for proper voltage output.
• Repair or replace damaged wiring or connectors.
• Replace the reductant quality sensor if faulty.
• Drain and refill the DEF tank with fresh, correct fluid.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-Series
• Chevrolet Silverado
• Ram 1500
• Regularly check and maintain DEF levels.
• Use only high-quality DEF fluid.
• Perform routine inspections of the SCR system.
Sensor Issue
• Avoid driving long distances until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code is relatively common in diesel vehicles equipped with SCR systems, especially if low-quality DEF is used.
Moderate – It's important to address this issue to ensure the vehicle meets emissions standards and operates efficiently.
Driving with a malfunctioning emissions system may violate environmental regulations and could lead to fines.
• Vehicle at operating temperature
• DEF tank filled with fresh fluid
The reductant quality sensor is typically located near the DEF tank or within the SCR system.
Q: Can I drive with a P206D code?
A: It's not recommended as it may lead to increased emissions and potential engine performance issues.
Q: How often should I check my DEF fluid?
A: Check your DEF fluid level regularly, especially before long trips, and refill as needed.
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