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 thinks there's a problem with the sensor that checks the quality of a special fluid used to reduce pollution. It's like when your nose tells you something smells funny.
The reductant quality sensor monitors the quality of the diesel exhaust fluid (DEF) used in the vehicle's selective catalytic reduction (SCR) system. This code indicates a low voltage signal from this sensor.
The P206C code is triggered when the powertrain control module (PCM) detects a lower than expected voltage from the reductant quality sensor circuit. This sensor is responsible for ensuring that the DEF meets the required quality standards for effective emissions reduction.
• Check Engine Light (CEL) illuminated
• Possible reduction in engine performance
• Increased emissions
• Faulty reductant quality sensor
• Wiring issues such as shorts or open circuits
• Poor electrical connections
Reductant: A substance that reduces emissions in diesel engines.
SCR: Selective Catalytic Reduction, a system that reduces 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 quality sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant quality sensor if faulty.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado
• Dodge Ram 2500
• Regularly check and maintain DEF quality.
• Inspect wiring and connectors periodically.
• Ensure the use of high-quality DEF.
Sensor Issue
• Avoid ignoring the check engine light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of SCR systems in diesel engines to meet emissions standards.
Moderate – While the vehicle may still be drivable, addressing emissions-related issues promptly is important to avoid further problems.
Driving with a malfunctioning emissions system may violate emissions laws and result in fines.
• Engine at operating temperature
• Vehicle driven under normal conditions
The reductant quality sensor is typically located near the DEF tank or in the DEF supply line.
Q: Can I drive with a P206C code?
A: While you may be able to drive, it's best to address the issue soon to avoid potential emissions violations and engine performance issues.
Q: What is Diesel Exhaust Fluid (DEF)?
A: DEF is a fluid used in diesel engines to reduce harmful emissions. It's sprayed into the exhaust stream to break down pollutants.
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