Reductant Quality Sensor Range/Performance Problem
There's an issue with the reductant quality sensor detecting the quality of the diesel exhaust fluid (DEF).
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 reductant quality sensor is supposed to check if the DEF is good for the emissions system. If the fluid is not right, it can cause pollution and engine problems. The sensor should see specific conductivity and temperature readings to confirm the DEF quality.
What the computer is actually seeing
The engine control module (ECM) measures the input from the reductant quality sensor, looking for proper conductivity values, typically ranging from 1000 to 2000 µS/cm under normal conditions. Any significant deviation from this range triggers the fault code.
What a healthy reading looks like
Conductivity: 1000-2000 µS/cm; Temperature: 0-40°C (32-104°F)
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.
- 1Inspect the DEF quality and ensure it meets manufacturers specs (ISO 22241).
- 2Check the wiring and connectors for the reductant quality sensor for damage or corrosion.
- 3Measure the conductivity of the DEF using a conductivity meter; it should be within 1000-2000 µS/cm.
- 4Verify the sensor's output voltage when the fluid is applied; it should correspond to expected values for good DEF.
- 5If defective, replace the reductant quality sensor and perform a system reset.
Common causes
- Faulty reductant quality sensor
- Contaminated or poor-quality DEF
- Wiring issues or damaged connectors to the sensor
- ECM software issues
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix it soon to avoid issues with emissions and potential damage to the exhaust system.
Will this issue come back after clearing the code?
If the underlying issue isn't fixed, yes, the code is likely to reappear.
Why does this code sometimes pair with others?
It can occur alongside other exhaust system codes if multiple components are failing or if there's a systemic issue affecting fluid quality.
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