Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble reading a sensor that checks the quality of a special fluid used to reduce pollution from the engine.
The P206B code indicates that the reductant quality sensor is not performing within its expected range. This sensor checks the quality of the Diesel Exhaust Fluid (DEF) used in the vehicle's Selective Catalytic Reduction (SCR) system.
The reductant quality sensor monitors the concentration and quality of the Diesel Exhaust Fluid (DEF) in the SCR system. If the sensor detects that the DEF quality is outside the specified range, it triggers the P206B code. This can affect the efficiency of the SCR system in reducing nitrogen oxide emissions.
• Check Engine Light illuminated
• Reduced engine performance
• Increased emissions
• Faulty reductant quality sensor
• Contaminated or incorrect DEF
• Wiring or connector issues in the sensor circuit
Reductant: A fluid used in diesel engines to reduce emissions.
SCR: Selective Catalytic Reduction, a system that reduces nitrogen oxide emissions in diesel engines.
• Check the DEF for contamination or incorrect fluid.
• Inspect the wiring and connectors of the reductant quality sensor.
• Test the reductant quality sensor for proper operation.
• Replace contaminated or incorrect DEF.
• Repair or replace faulty wiring or connectors.
• Replace the reductant quality sensor if defective.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Use only high-quality DEF.
• Regularly inspect the DEF system for leaks.
• Keep the DEF tank clean and free from contaminants.
Sensor Issue
• Ensure DEF is filled with the correct fluid.
• Regularly check for any warning lights on the dashboard.
Check with your 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 – Addressing this issue promptly can prevent increased emissions and potential engine performance issues.
Ignoring emissions-related codes can lead to failing emissions tests and potential fines.
• Engine running
• Vehicle at operating temperature
The reductant quality sensor is typically located near the DEF tank or within the DEF line.
Q: Can I drive with a P206B code?
A: While the vehicle may still be drivable, it's important to address the issue to avoid increased emissions and potential engine performance problems.
Q: What happens if I ignore the P206B code?
A: Ignoring the code can lead to increased emissions, potential engine performance issues, and failing emissions tests.
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