WOMS
P code powertrain Medium severity

P205D Reductant Tank Temperature Sensor Circuit High

The OBD2 code P205D indicates that the reductant tank temperature sensor circuit is reporting a high voltage or signal, which may suggest a malfunction in the sensor or its wiring

Definition

The OBD2 code P205D indicates that the reductant tank temperature sensor circuit is reporting a high voltage or signal, which may suggest a malfunction in the sensor or its wiring

Common causes

  • Faulty reductant tank temperature sensor
  • Open or shorted wiring in the sensor circuit
  • Poor electrical connections or corroded connectors
  • Faulty engine control module (ECM)
  • Incorrect sensor calibration or installation
  • High resistance in the sensor circuit
  • Environmental factors affecting sensor performance

Common misdiagnoses

  • Faulty reductant tank temperature sensor
  • Wiring issues or short circuits in the sensor circuit
  • Faulty engine control module (ECM)
  • Incorrectly diagnosed fuel system issues
  • Misinterpretation of related OBDII codes
  • Issues with the reductant pump or injector
  • Problems with the DEF (diesel exhaust fluid) quality or level
  • Faulty connectors or terminals in the sensor circuit

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other related trouble codes. This can provide more context and help identify if there are multiple issues

  2. 2. Inspect the Reductant Tank Temperature Sensor

    Locate the reductant tank temperature sensor and visually inspect it for any signs of damage, corrosion, or loose connections

  3. 3. Ensure that the sensor is properly connected and that the wiring harness is intact

  4. 4. Test the Sensor

    Use a multimeter to test the resistance of the temperature sensor. Compare the readings to the manufacturer's specifications

  5. 5. If the resistance is outside the specified range, the sensor may be faulty and need replacement

  6. 6. Check the Wiring and Connectors

    Inspect the wiring and connectors leading to the reductant tank temperature sensor for any signs of wear, fraying, or corrosion

  7. 7. Repair or replace any damaged wiring or connectors

  8. 8. Check for Short Circuits

    Use a multimeter to check for short circuits in the wiring harness. A short to power could cause the circuit to read high

  9. 9. Disconnect the sensor and check the voltage at the connector with the ignition on. If the voltage is higher than expected, there may be a short in the wiring

  10. 10. Inspect the Reductant Tank

    Check the reductant tank for any signs of contamination or damage that could affect the sensor's operation

  11. 11. Ensure that the tank is filled with the correct type of reductant fluid (e.g., DEF - Diesel Exhaust Fluid)

  12. 12. Check the Engine Control Module (ECM)

    If all other components check out, there may be an issue with the ECM or its programming. Ensure that the ECM is functioning correctly and that it has the latest software updates

  13. 13. Clear the Codes and Test Drive

    After performing repairs or replacements, clear the trouble codes using the OBD-II scanner

  14. 14. Take the vehicle for a test drive to see if the code returns. Monitor the performance of the SCR system and the temperature readings

  15. 15. Consult Technical Service Bulletins (TSBs)

    Check for any TSBs related to the P205D code for your specific vehicle make and model. Manufacturers may have issued guidance or fixes for known issues

  16. 16. Seek Professional Help

    If the issue persists after following these steps, it may be best to consult a professional mechanic or technician who has experience with diesel engines and SCR systems. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P205D code