Your Sprinter uses upstream and downstream NOx sensors to measure how well the SCR system is scrubbing emissions. A drifting sensor triggers check engine lights and DEF faults even when dosing is fine. We test both sensors, replace the failed one, and code it so readings match again.
What this service includes
- Compare upstream and downstream NOx readings in live data
- Isolate the failed sensor from the SCR catalyst itself
- Replace the correct NOx sensor with a genuine unit
- Code the sensor and confirm the values track properly
Signs your Sprinter needs it
- Check engine light with NOx or SCR efficiency codes
- DEF warning appears with no dosing complaint
- NOx sensor readings that stay flat or read implausible
What does nox sensor calibration cost?
Ballpark pricing for nox sensor calibration on a Sprinter runs $450 to $1,500. The final number depends on your model, mileage, and the exact cause, which we confirm with Xentry before any work is authorized. Diagnostic time is credited toward the repair. See the full pricing page.
Frequently asked questions
Which NOx sensor is bad on my Sprinter?
There are two, and the code alone does not always say which. We compare their live readings so we replace the failed sensor instead of both, which keeps your Riverside repair honest.
Do NOx sensors need coding after replacement?
Yes. The new sensor has to be written to the module so its baseline matches the system, otherwise the fault returns. We always code and verify before we hand the van back.