The P205C: Reductant Tank Temperature Sensor Circuit Low refers to a fault where the reductant tank temperature sensor circuit is experiencing low voltage. This sensor monitors the temperature of the diesel exhaust fluid (DEF) in the reductant tank. Low voltage in the circuit may cause inaccurate temperature readings, which can affect the emission control system’s performance. This issue may arise from a faulty sensor, wiring problems, or connector issues.
P205C – Quick Overview
| Code | Information |
|---|---|
| Meaning | P205C: Reductant Tank Temperature Sensor Circuit Low |
| Is it serious? | Yes, it can lead to incorrect temperature monitoring, reducing the effectiveness of the emissions control system. |
| 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 |
P205C Meaning
The P205C code indicates that the reductant tank temperature sensor circuit is experiencing low voltage, which can cause the temperature sensor to malfunction. This sensor ensures that the DEF in the reductant tank is within the optimal temperature range for injection into the exhaust system to reduce emissions. A low voltage condition can prevent the sensor from accurately reading the temperature, which may result in improper reductant dosing and increased emissions.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to search for additional codes that might provide further insight into the fault. | OBD-II Scanner |
| Measure Voltage in the Circuit | Measure the voltage in the reductant tank temperature sensor circuit to determine if it is below the manufacturer’s specified range. | Multimeter |
| Test the Sensor | Use a diagnostic tool to test the sensor and ensure it is functioning correctly within the proper voltage range. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connectors | Check the wiring and connectors for signs of damage, corrosion, or loose connections that could result in low voltage or sensor failure. | Flashlight, Multimeter |
| 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 has been resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the vehicle after the test drive to ensure that the P205C code does not reappear. If it returns, further diagnostics may be needed. | OBD-II Scanner |
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