Mercedes-Benz has long been recognised for its premium-quality vehicles, with a particular focus on delivering powerful yet efficient diesel engines. Among their diesel lineup, the E-Class models, specifically the W213, S213, C238, and A238, stand out. These vehicles are designed with luxury, performance, and technology at their core. The W213, introduced in 2016, set new standards for innovation within the E-Class range, followed by the S213 (wagon version), C238 (coupe), and A238 (convertible), each enhancing the driving experience in its unique way.
Mercedes-Benz diesel engines, found in these E-Class models, rely on advanced emission control systems, including NOx (nitrogen oxide) sensors, to maintain their environmental standards. These sensors are essential for monitoring emissions and ensuring that diesel engines run cleanly and efficiently. However, like all components, NOx sensors can occasionally develop faults, leading to diagnostic trouble codes (DTCs) that may affect the vehicle's performance.
In this blog, we will break down NOx sensors, discuss their role in Mercedes-Benz diesel engines, and explain some of the most common fault codes you may encounter. By understanding these codes, drivers can gain insight into potential issues and the necessary steps to address them.
A Brief Overview of NOx Sensors
NOx sensors play a crucial role in diesel vehicles, specifically for emission control. These sensors measure the levels of nitrogen oxides in the exhaust system, which are harmful pollutants produced by combustion. The information gathered by NOx sensors helps the vehicle's engine control unit (ECU) adjust fuel and air mixture to reduce emissions and improve fuel efficiency. In Mercedes-Benz diesel models, NOx sensors are placed both upstream and downstream of the SCR (Selective Catalytic Reduction) catalytic converter, where they closely monitor the emissions output.
In our focus on Mercedes-Benz E-Class models (W213, S213, C238, and A238), NOx sensors are key to keeping emissions within regulatory limits. When these sensors detect issues, they may trigger specific diagnostic trouble codes.
Understanding Diagnostic Trouble Codes (DTCs)
Diagnostic trouble codes, or DTCs, are alphanumeric codes stored by the ECU when it detects a malfunction in the vehicle’s system. These codes serve as a tool for identifying the specific problem area, allowing mechanics or the vehicle owner to understand what component or system needs attention. In the case of Mercedes-Benz diesel models, certain DTCs are linked directly to the NOx sensor’s performance.
Fault codes related to the NOx sensor generally indicate an issue with the sensor itself or the sensor’s circuitry. If the NOx sensor fails to perform correctly, it will be reflected through these fault codes, which can be read through a diagnostic scan. By identifying these codes, drivers can gain a better understanding of any emission-related issues affecting their vehicle.
Why Does the NOx Sensor Fail?
Like any other electronic component, the NOx sensor in Mercedes-Benz diesel engines has a natural lifespan. Over time, continuous exposure to high temperatures and exhaust gases gradually wears down the sensor, reducing its effectiveness. This is a common issue in diesel vehicles and doesn’t necessarily indicate a defect; instead, it reflects the sensor’s normal ageing process. Eventually, the sensor can no longer accurately measure nitrogen oxide levels, leading to diagnostic fault codes and potential performance issues. Replacing a failed NOx sensor is therefore a routine maintenance requirement for diesel cars, particularly as they age or accumulate higher mileage.
How to Fix a Failed NOx Sensor in Mercedes-Benz E-Class Models (W213, S213, C238, A238)
In Mercedes-Benz E-Class diesel models like the W213, S213, C238, and A238, the NOx sensor is located upstream, positioned before the SCR catalytic converter. Known as "sensor 1" or the "upstream sensor," it plays a key role in monitoring and reducing emissions. If your vehicle has displayed any of the NOx sensor fault codes, replacing this sensor is necessary to restore proper emissions control.
To replace the sensor:
- Remove the old NOx sensor from its location upstream of the SCR catalytic converter.
- Install the new sensor in the same location.
- Once the new sensor is installed, start the car and drive it briefly to allow the ECU to recognise the replacement. The check engine light should turn off shortly, confirming the issue is resolved.
You can purchase the correct NOx sensor for your E-Class diesel model through Xenons4u's site. Here is the link to the product, which includes the compatible Mercedes-Benz part numbers:
- A0009058011
- MA0009058011
- A000 905 80 11
- A000905801180
- A000905801187
- MA000905801180
- MA000905801187
Continental part numbers include SNS1005 A3C01057500-01 and SNS1005A A3C06300500-01.
More compatible part numbers:
- A0009053009 SNS381B A2C15462900-02
- A0009054704 SNS381A A2C12776200-01
- A0009057108 SNS381A A2C12776200-01
- A0009059112 SNS1048 A3C03950800-01
- MA000905911264 A000905911264
- A0009050914 SNS1116 AAA2082120000
Common Diagnostic Trouble Codes (DTCs) for NOx Sensor Issues
The following DTCs may indicate a fault with the NOx sensor in Mercedes-Benz E-Class diesel models:
- P2201 NOx sensor circuit range/performance bank 1 sensor 1
- P2200 Nitrogen Oxide NOx sensor Circuit Bank 1
- P2201 Nitrogen Oxides NOx sensor 1 bank 1 Range Performance problem
- P2201 NOx sensor Circuit Range/Performance bank 1
- P2201 Nitrogen Oxides NOx sensor bank 1 - range/performance problem
- P300637 - NOx sensor 1 bank 1 Faulty operation
- P300637 The NOx sensor 1 (cylinder bank 1) has a malfunction
- P3009EC Component NOx sensor Upstream of SCR Catalytic Converter has a malfunction
- P3009EC NOx sensor Circuit Range/Performance Bank 1 Sensor 1
- P3009EC NOx sensor 1 bank 1 Electrical fault
- P3009EC Le capteur NOx 1 (banc de cylindres 1) presente un defaut de fonctionnement
- P300637 The Component NOx sensor Upstream of SCR Catalytic Converter has a sporadic malfunction
- P300651 Component NOx sensor Upstream of SCR Catalytic Converter has a malfunction
- P300651 NOx sensor (bank 1) faulty operation
- P300651 The NOx sensor (cylinder bank 1) is faulty
- P300651 The NOx sensor 1 (cylinder bank 1) has a malfunction
- P300640 The NOx sensor 1 (cylinder bank 1) has an electrical fault
- P300640 An electrical fault exists in the NOx sensor (cylinder bank 1)
- P30063F The NOx sensor 1 (cylinder bank 1) has an electrical fault
- P30063F An electrical fault exists in the NOx sensor (cylinder bank 1)
- P30067E The NOx sensor 1 (cylinder bank 1) has a malfunction
- P30067E The NOx sensor (cylinder bank 1) is faulty
- P30067E Component NOx sensor Upstream of SCR Catalytic Converter has A malfunction. The signal comparison is faulty
- P300640 Senzor NOx (Banc 1) Defect electric
- P30063F Senzor NOx (Banc 1) Defect electric
- P300677
- P300640 Component NOx sensor Upstream of SCR Catalytic Converter has an electrical fault. There is a short circuit to ground
- P30063F Component NOx sensor Upstream of SCR Catalytic Converter has a malfunction. There is an open circuit
- P30064C The efficiency of the SCR catalytic converter (cylinder bank 1) is not sufficient
- P204F Adblue system bank 1 malfunction
- P13DF Adblue system malfunction
- U029D00 La comunicación con el sensor de NOx 1 tiene una irregularidad de funcionamiento
- U029D87 La comunicación con el sensor de NOx 1 tiene una irregularidad de funcionamiento. Falta el mensaje
- P19D800 NOx sensor circuit upstream electrode peel off
- P30063C The NOx sensor 1 (cylinder bank 1) has a malfunction
- P229F NOx sensor Circuit Range/Performance Bank 2
- P300A62 Component NOx Sensor Upstream Of SCR Catalytic Converter Has A Malfunction.
- P30063C Component NOx Sensor Upstream Of SCR Catalytic Converter Has A Malfunction. There Is A Component Fault
- P300637 The NOx sensor 1 Cylinder bank 1 has a malfunction
- P300642 Component NOx sensor downstream of SCR catalytic converter has a malfunction. The function or the instruction is faulty
- P300644 Component NOx sensor downstream of SCR catalytic converter has a malfunction. There is a signal above the permissible limit value
If you encounter any of these codes, replacing the NOx sensor is often the best solution to restore performance and clear the check engine light.
Here is a list of compatible Mercedes cars:
Compatible Mercedes cars:
- A class W177 Hatchback
- A class V177 Saloon Sedan
- A160d A180d A200d A220d diesel AMG Line
- GLE V167 W167 SUV 2019 2020 2021 2022
- GLE300d GLE350d GLE350de
- GLE400d 4MATIC AMG Line
- C class W205 S205 C205 Facelift 2018 2019 2020
- C180d C200d C220d C300d BlueTEC 4MATIC
- C350de C350h Plug-In Hybrid
- E Class W213 Saloon Sedan 2016 2017 2018 2019 2020
- E Class S213 Estate Wagon
- E class C238 Coupe 2017 2018 2019
- E200d E220d E300d E400d diesel bluetec 4Matic
- E300de Mild Hybrid
- SE Sport AMG Line Automatic
- CLS W257 C257 Coupe 2018 2019 2020 2021 2022
- CLS400d 4MATIC
- CLS350d 4-matic
- Sprinter W907 W910 Van Bus
- Sprinter 1500 2500 3500
- V class W447 Viano Vito
- CLA C117 X117
- GLE C292 Coupe
- G class W463
- S class W222 Facelift 2017 2018 2019 2020
- S350d S400d BlueTEC 4MATIC diesel
- AMG Line Executive Premium Plus
- Sprinter W907 907 VS30 Bus
- Sprinter W910 910 VS30 Van Panel Van
- Sprinter Tourer 319 CDI 4x4
- 2018 2019 2020 2021
- Sprinter 2500 3500 4500 3.0 diesel
- Winnebago Vita Class C RV Sprinter chassis
- X class W470 Pickup X350d 3.0L V6
With the correct part and a straightforward installation, replacing a failed NOx sensor is a manageable task that ensures your Mercedes-Benz diesel engine continues to meet emissions standards and operates at its best.
