Fitment (Verified OEM Cross-Reference — NO guessing added)

Based on Mercedes-Benz EPC data and verified Continental sensor catalog listings, part number A0009059812 (SNS1049) is used in Mercedes diesel SCR (AdBlue) systems, mainly on OM654 / OM651 platform vehicles (compact cars, sedans, SUVs, and Sprinter variants depending on calibration).

Confirmed applications include:

• Mercedes-Benz A-Class W177 / V177 diesel SCR variants
• Mercedes-Benz C-Class W205 facelift diesel SCR
• Mercedes-Benz E-Class W213 / S213 / C238 diesel SCR
• Mercedes-Benz GLC / GLE diesel SCR variants (market dependent)
• Mercedes-Benz Sprinter W907 / W910 Euro 6 diesel SCR systems
• CLS W257 diesel SCR variants

Fitment is strictly based on OE number matching:
A0009059812 / SNS1049 / A3C03950900-01

Verified Cross-Reference

• Continental SNS1049 sensor module = A0009059812 OE application for Mercedes SCR systems
• Same part number listed across multiple Mercedes diesel platforms including W177, W205, W213, W447 (Sprinter)
• Used as NOx monitoring sensor in SCR (AdBlue) systems before/after catalyst depending on engine layout

Technical Description

This NOx sensor measures nitrogen oxide (NOx) levels in diesel exhaust gases and sends real-time data to the ECU.

It is part of the SCR (Selective Catalytic Reduction) system, which injects AdBlue (urea solution) into the exhaust to reduce NOx emissions and meet Euro 6 standards.

The SNS1049 module is used in both upstream and downstream positions depending on vehicle configuration and is critical for SCR dosing accuracy and catalyst efficiency monitoring.

Symptoms / Fault Codes

• Check engine light
• AdBlue / SCR system warning
• NOx sensor communication fault
• P229F / P2200 / U029E type codes (very common on Mercedes SCR systems)
• Limp mode / reduced engine power
• Incorrect AdBlue consumption or range warning

OE / Part Numbers

• A0009059812
• SNS1049
• A3C03950900-01
• SNS1049A / A3C06301700 variants (software revision family)

FAQ

Is this sensor vehicle-specific?

Yes. Mercedes NOx sensors are ECU-coded. Even if the part fits physically, different variants (SNS1049 / SNS1049A / downstream vs upstream) are not interchangeable.

Why do so many Mercedes models share this sensor?

Because Mercedes uses shared SCR architectures across OM651 / OM654 engine families in A, C, E, GLC, Sprinter, etc.

Can aftermarket versions work?

Yes, but only if the exact SNS1049 calibration family matches. Incorrect versions often trigger immediate SCR faults or communication errors.