The P205A: Reductant Tank Temperature Sensor Circuit refers to a fault in the circuit responsible for monitoring the temperature of the reductant tank, which holds diesel exhaust fluid (DEF) for emissions control. This issue can cause the system to improperly monitor or regulate the temperature of the reductant, leading to potential problems with the vehicle’s emissions system. Common causes include a faulty sensor, wiring issues, or problems within the sensor circuit.
P205A – Quick Overview
| Code | Information |
|---|---|
| Meaning | P205A: Reductant Tank Temperature Sensor Circuit |
| Is it serious? | Yes, this can cause improper reductant dosing, leading to increased emissions and reduced system performance. |
| Possible causes | – Faulty reductant tank temperature sensor – Wiring or connector issues – Sensor circuit problems |
| How to diagnose? | – Test the reductant tank temperature sensor – Inspect wiring and connectors – Check the sensor circuit for issues |
P205A Meaning
The P205A code indicates a problem with the reductant tank temperature sensor circuit. This sensor monitors the temperature of the DEF in the reductant tank, ensuring that it remains within the optimal range for proper dosing into the exhaust system. When the circuit is faulty, it can lead to incorrect readings or failure to monitor the temperature, which may negatively impact emissions control and overall system performance.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for related codes that may provide additional insight into the issue. | OBD-II Scanner |
| Test the Temperature Sensor | Use a diagnostic tool or multimeter to test the reductant tank temperature sensor to verify it is functioning within the correct range. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connectors | Check the wiring and connectors connected to the sensor for any signs of damage, corrosion, or loose connections that could cause circuit issues. | Flashlight, Multimeter |
| Check the Sensor Circuit | Inspect the entire sensor circuit for potential issues such as shorts, open circuits, or faulty connections that could affect the sensor’s accuracy. | Multimeter, Circuit Tester |
| Clear the Code and Test Drive | After repairs, clear the fault code using an OBD-II scanner and perform 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 system to ensure that the P205A code does not return. If it reappears, further diagnosis is required. | OBD-II Scanner |
Free PDF: How to choose OBD2 scanner
I’ve made you a free PDF to choose the OBD2 scanner in 5 minutes.
✅ Which OBD2 scanner is best?
✅ Which type should you get (DIY, Pro, Hobby)
✅ What is the best scanner for the exact brand/feature (e.g best for BMW)
✅ How to get a Bi-Directional tool for as cheap as $40
✅ Discount coupons for scanners
PDF is 100% free and it is designed to help you pick a scanner in less than a few minutes! Not a boring 50-page guide.
Just tell me where to send it.
Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)