Mercedes NOx sensor faults affecting the SCR and AdBlue emissions system, including warning lights, SCR faults and AdBlue system issues.
NOx sensor faults can trigger SCR and AdBlue system warnings along with engine management faults.
Live diagnostic data is used to verify NOx sensor readings and communication with the engine control unit.
If sensor values remain implausible after checking wiring and connections, the NOx sensor is typically confirmed faulty.
Mercedes diesel engines commonly use both upstream and downstream NOx sensors, so correct sensor identification is important before replacement.
Genuine Mercedes-Benz sensors are generally recommended, as some aftermarket sensors can cause communication faults or recurring warning messages.
Mercedes SCR systems rely on accurate NOx sensor readings for AdBlue dosing and emissions control. Incorrect sensor readings may trigger SCR efficiency faults, warning messages or repeated fault codes.