Reductant Temperature Sensor Range/Performance Problem
This code indicates an issue with the temperature sensor for the reductant (urea) system.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The temperature sensor in the diesel exhaust fluid (DEF) system is reading temperatures that are out of normal range, which can affect emissions control.
What the computer is actually seeing
The engine control unit (ECU) monitors the reductant temperature sensor signal. It expects smooth voltage changes, typically between 0.5V to 4.5V, corresponding to temperatures from -40°C to 80°C. Out-of-range signals flag this code.
What a healthy reading looks like
Reductant temperature range should be between 0°C and 80°C. Sensor voltage should range from 0.5V (low temp) to 4.5V (high temp).
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check DEF level; it should be within operational range (min 1/4 tank) before diagnostics.
- 2Inspect the wiring and connectors for signs of damage or corrosion. Repair if necessary.
- 3Monitor the sensor voltage at the ECU connector; it should range from 0.5V to 4.5V depending on temperature.
- 4If voltage is out of range, replace the reductant temperature sensor and test again.
- 5Clear the code and see if it returns after a drive cycle.
Common causes
- Wiring issues (frayed, shorted, or open circuits)
- Faulty reductant temperature sensor
- Connector corrosion or damage
- Temperature sensor frozen due to low ambient temperatures
Typical repair cost
$$
Related codes
Frequently asked questions
Can I still drive the vehicle with this code?
Yes, but you might face reduced emissions performance and increased DEF usage.
Will this code come back after clearing?
If the root cause isn't fixed, the code is likely to return after driving a short distance.
Why does this relate to other codes like P207F?
Codes like P207F relate to different aspects of the DEF system and often appear together when there's a broader issue.
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