Mercedes W220 S350 M112.972 245HP Engine Module ECU A1121535379 Automatic

The Mercedes W220 S350 M112.972 245HP Engine Control Module is a specialized electronic engine controller designed for versions with an automatic transmission and petrol fuel. It is responsible for precise management of the powertrain's operation, ensuring proper communication with other vehicle systems. A used ECU is a sensible choice for professional repair or replacement of a damaged module in S-Class cars.

Specifications and technical data

• SKU: A1121535379
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1121535379
• Substitutable numbers: A1121535379, A 112 153 53 79, 0261208425, 0 261 208 425
• Fuel type: Petrol
• Gearbox type: Automatic
• Category: ECUs & Computer Modules

Purpose and Function of the Engine Controller

The presented electronic control module belongs to the group of Electronic Control Units and Controllers and is dedicated to the petrol engine in the Mercedes S-Class W220 generation, S350 version. The ECU manages, among other things, fuel injection, ignition, and cooperation with the automatic transmission, which is crucial for stable engine operation, smooth acceleration, and correct response to loads.

Thanks to its factory architecture, the module collaborates with the vehicle's onboard network, safety systems, and OBD diagnostic systems, enabling correct error readings and their subsequent analysis in the service center.

Benefits of Using an Original ECU

Using an original engine controller in the Mercedes W220 S350 allows for compliance with the factory operating parameters of the M112.972 engine. In practice, this means:

• correct cooperation with the automatic transmission,
• stable idle speed and predictable throttle response,
• consistency with factory ignition and injection maps for the petrol engine,
• easier diagnostics and servicing based on standard Mercedes procedures.

A used ECU module is a solution that helps reduce repair costs while maintaining high quality and full functionality of the engine control system.

Application in Vehicles with Automatic Transmission

The controller is designed to work with an automatic transmission, so its configuration includes data exchange with the transmission control module. This is important for:

• smooth gear changes under load,
• coordination of engine torque with transmission logic,
• reduction of jerks and unwanted drivetrain overloads.

This allows the controller to support comfortable, predictable driving, characteristic of S-Class sedans.

Professional Selection and Installation

To select the appropriate ECU module for a specific Mercedes model, it is recommended to verify compatibility by OEM number, interchangeable numbers, and vehicle data (VIN, engine version, transmission type). A correctly selected controller minimizes the risk of CAN network communication problems, engine malfunctions, or the need for time-consuming adaptation.

If you have doubts regarding the selection, programming, or adaptation of a used controller, it is worth consulting the practical guide from Global Parts – detailed information can be found in the article Used Automotive Electronics Onboard – Why Choose Second-Hand ECUs and Sensors?.

Expansion of the Control System in Mercedes

If you are planning a comprehensive repair or modernization of the engine area in your Mercedes and need other components from the same group, such as additional controllers, engine management modules, or controllers cooperating with the ECU, check the available parts in the category Mercedes Electronic Control Units and Controllers.

Choosing a used control module is also a step towards a more responsible approach to vehicle operation – reusing functional electronic components reduces waste and allows for efficient management of the service budget.