The P206B: Reductant Quality Sensor Circuit Range/Performance refers to a fault where the reductant quality sensor is not performing within the expected range. This sensor monitors the quality of the diesel exhaust fluid (DEF) used in the vehicle’s emissions control system. A performance issue could result from a faulty sensor, incorrect readings, or problems with the wiring and connectors.
P206B – Quick Overview
Code | Information |
---|---|
Meaning | P206B: Reductant Quality Sensor Circuit Range/Performance |
Is it serious? | Yes, it can lead to improper monitoring of the DEF quality, affecting the emission control system’s efficiency. |
Possible causes | – Faulty reductant quality sensor – Incorrect sensor performance – Wiring or connector issues |
How to diagnose? | – Test the sensor for range and performance – Inspect wiring and connectors – Verify sensor operation |
P206B Meaning
The P206B code indicates that the reductant quality sensor is not operating within the expected range or performance standards. This sensor ensures that the DEF in the system meets the required quality for optimal emissions reduction. If the sensor is not functioning correctly, it could cause inaccurate readings of DEF quality, potentially leading to increased emissions or system malfunctions.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to search for any additional codes that may provide further information about the issue with the reductant system. | OBD-II Scanner |
Test the Sensor for Range/Performance | Use a diagnostic tool or multimeter to test the reductant quality sensor and verify that it is operating within the proper range and providing accurate readings. | Multimeter, Diagnostic Tool |
Inspect Wiring and Connectors | Check the wiring and connectors leading to the reductant quality sensor for signs of damage, corrosion, or loose connections that could affect performance. | Flashlight, Multimeter |
Verify Sensor Operation | Confirm that the reductant quality sensor is working as per the manufacturer’s specifications and ensure it provides accurate data. | Diagnostic Tool |
Clear the Code and Test Drive | After repairs, clear the code with an OBD-II scanner and take the vehicle for a test drive to confirm the issue has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P206B code does not return. If the code reappears, further diagnostics may be necessary. | OBD-II Scanner |

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