The P206C: Reductant Quality Sensor Circuit Low refers to a fault where the reductant quality sensor circuit is experiencing low voltage. This sensor monitors the quality of the diesel exhaust fluid (DEF) in the system. Low voltage can lead to inaccurate DEF quality readings, which can affect the performance of the emissions control system. Common causes include a faulty sensor, wiring problems, or connector issues.
P206C – Quick Overview
| Code | Information |
|---|---|
| Meaning | P206C: Reductant Quality Sensor Circuit Low |
| Is it serious? | Yes, it can lead to improper monitoring of DEF quality, potentially causing emissions system malfunctions. |
| Possible causes | – Low voltage in the sensor circuit – Faulty sensor – Wiring or connector issues |
| How to diagnose? | – Measure voltage in the sensor circuit – Test the sensor – Inspect wiring and connectors |
P206C Meaning
The P206C code indicates that the reductant quality sensor circuit is receiving a lower voltage than expected. This sensor is responsible for monitoring the quality of DEF in the vehicle’s emissions control system. A low voltage signal may cause inaccurate readings, which can result in improper DEF dosing and increased emissions. The problem may lie in the sensor itself, wiring, or connectors.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any additional fault codes that may provide more information on the sensor circuit issue. | OBD-II Scanner |
| Measure Voltage in the Circuit | Use a multimeter to measure the voltage in the reductant quality sensor circuit and compare it to the manufacturer’s specifications to confirm low voltage. | Multimeter |
| Test the Sensor | Use a diagnostic tool to test the reductant quality sensor for proper operation, ensuring it’s functioning within the expected voltage range. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connectors | Inspect the wiring and connectors leading to the sensor for any signs of damage, corrosion, or loose connections that may cause low voltage. | Flashlight, Multimeter |
| Clear the Code and Test Drive | After repairs, clear the fault code with an OBD-II scanner and take the vehicle for a test drive to ensure 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 that the P206C code does not return. If it reappears, further diagnostics may be needed. | OBD-II Scanner |
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