SCR Reductant Quality Sensor Failure
Failure detected in the SCR reductant quality sensor.
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 SCR reductant quality sensor measures the quality of the diesel exhaust fluid (DEF). If it detects that the fluid isn't within the expected range, it flags a fault. This usually means the DEF is either contaminated or the sensor itself is malfunctioning.
What the computer is actually seeing
The engine control unit monitors the voltage and resistance from the reductant quality sensor to determine if the DEF quality is adequate. It expects to see a specific voltage range (typically between 0.5 to 2.5 volts) corresponding to a specific quality of DEF.
What a healthy reading looks like
The sensor should output between 0.5V (good quality) to 2.5V (bad quality).
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 the level and quality of the diesel exhaust fluid (DEF) in the tank. Ensure it's not contaminated with water or any other substance.
- 2Inspect the wiring harness and connector for the SCR reductant quality sensor. Look for damage, corrosion, or loose connections.
- 3Test the voltage output of the SCR reductant quality sensor. Expect to see between 0.5V to 2.5V. A voltage outside this range indicates a problem with the sensor.
- 4If the sensor output is within range but the code persists, consider replacing the SCR reductant quality sensor.
Common causes
- Contaminated DEF
- Faulty SCR reductant quality sensor
- Wiring issue with sensor harness
- Poor electrical connection at sensor or ECM
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not advisable to drive for extended periods with this fault, as it can affect emissions and vehicle performance.
Will this code come back after clearing?
If the underlying issue isn't fixed, the code will likely return.
Why does this code appear with other codes?
This code often pairs with DEF quality issues which may involve other components like the pump or tank.
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