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 has detected a problem with the sensor that checks the quality of a special liquid used to reduce pollution from the exhaust. It's like a sensor that checks if the liquid is good or bad.
The P206A code is triggered when the engine control module (ECM) detects an issue with the circuit of the reductant quality sensor, which measures the quality of the diesel exhaust fluid (DEF).
The reductant quality sensor is responsible for monitoring the quality of the diesel exhaust fluid (DEF) used in the selective catalytic reduction (SCR) system. This sensor ensures that the DEF meets the necessary standards for reducing NOx emissions. A fault in the sensor circuit can affect the SCR system's efficiency and lead to increased emissions.
• Check Engine Light (CEL) is on
• Decreased fuel efficiency
• Increased emissions
• Faulty reductant quality sensor
• Damaged wiring or connectors in the sensor circuit
• DEF contamination or incorrect fluid
Reductant: A substance used to reduce emissions, often referring to DEF in diesel engines.
SCR: Selective Catalytic Reduction, a system used to reduce NOx emissions in diesel engines.
• Scan the vehicle with an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors of the reductant quality sensor for damage.
• Test the reductant quality sensor for proper operation.
• Replace the reductant quality sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Drain and refill the DEF tank with the correct fluid if contaminated.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly check and maintain DEF levels.
• Use high-quality DEF fluid.
• Inspect wiring and connectors periodically.
Sensor Issue
• Do not ignore the Check Engine Light.
• Ensure to use the correct DEF fluid.
• Consult a professional mechanic if unsure.
Check with your vehicle manufacturer as some emissions-related components may be covered under warranty.
This code has become more common with the increased use of DEF systems in diesel vehicles to meet emission standards.
Moderate – Addressing this issue is important to maintain vehicle emissions and performance.
Ignoring emissions-related codes can lead to failing emissions tests and increased pollution.
• Engine running
• DEF system active
The reductant quality sensor is typically located in or near the DEF tank.
Q: Can I drive with a P206A code?
A: While you may be able to drive, it's not recommended as it could lead to increased emissions and potential engine performance issues.
Q: What happens if I ignore this code?
A: Ignoring the code can result in increased emissions, potential damage to the SCR system, and failing emissions tests.
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