The P206A: Reductant Quality Sensor Circuit refers to a fault in the circuit that monitors the quality of the reductant, typically diesel exhaust fluid (DEF), used in the vehicle’s emissions control system. This issue could be caused by a faulty reductant quality sensor, wiring or connector issues, or circuit problems, which may lead to inaccurate readings of the DEF quality.
P206A – Quick Overview
Code | Information |
---|---|
Meaning | P206A: Reductant Quality Sensor Circuit |
Is it serious? | Yes, it can lead to inaccurate readings of the DEF quality, affecting the emissions control system’s performance. |
Possible causes | – Faulty reductant quality sensor – Wiring or connector issues – Sensor circuit problems |
How to diagnose? | – Test the reductant quality sensor – Inspect wiring and connectors – Check the sensor circuit for issues |
P206A Meaning
The P206A code indicates a problem with the reductant quality sensor circuit. This sensor monitors the quality of the DEF to ensure it meets the necessary standards for effective emissions reduction. When the sensor or its circuit is faulty, the system may not be able to detect if the DEF is contaminated or of poor quality, which can lead to performance issues in the selective catalytic reduction (SCR) system, resulting in increased emissions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional related fault codes that may provide further context on the reductant system issue. | OBD-II Scanner |
Test the Reductant Quality Sensor | Use a diagnostic tool or multimeter to test the reductant quality sensor and ensure it is functioning properly and within manufacturer specifications. | Multimeter, Diagnostic Tool |
Inspect Wiring and Connectors | Inspect the wiring and connectors for any signs of damage, corrosion, or loose connections that could affect the sensor’s performance. | Flashlight, Multimeter |
Check the Sensor Circuit | Examine the sensor circuit for any shorts, open circuits, or faults that could disrupt the proper functioning of the reductant quality sensor. | Multimeter, Circuit Tester |
Clear the Code and Test Drive | After completing repairs, clear the code with an OBD-II scanner and take the vehicle for a test drive to confirm the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P206A code does not return. If the code reappears, further diagnostics may be necessary. | OBD-II Scanner |

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