Mercedes W205 C253 W257 Door Module Rear Left N/S Control Unit ECU A1679003418

The Mercedes W205 C253 W257 Rear Left Door Module is an original component from the Electronic Control Modules group, designed to manage the functions of the rear left door. This used OEM part ensures proper communication with the vehicle's electrical system and maintains the factory parameters for comfort systems.

Specifications and technical data

• SKU: A1679003418
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1679003418
• Substitutable numbers: A1679003418, A 167 900 34 18
• Location on the vehicle: Rear, Left
• Category: ECUs & Computer Modules

Module Purpose and Function

The Rear Left Door Module is responsible for controlling and monitoring the components located in the rear left door of Mercedes vehicles from the W205, C253, and W257 series. Its task is to integrate signals from the body's electrical system and transmit them to the actuators in the door, according to the manufacturer's logic.

Its placement on the vehicle, specified as rear – left side, allows for unambiguous identification of the installation position and reduces the risk of errors in part selection. This enables the module to be integrated into the vehicle's existing network architecture without the need for wiring or connector modifications.

Compatibility and Vehicle Electronics Integration

As a component in the Electronic Control Modules and Controllers category, the module communicates with the vehicle's data bus, ensuring correct data exchange with other control units. Its appropriate hardware design and software tailored to the W205 / C253 / W257 platform allow for maintaining the consistency of the comfort and safety systems.

Being an original Mercedes part means it adheres to the manufacturer's factory quality standards, including electrical parameters, environmental resistance, and diagnostic requirements. The module has an assigned OEM part number and associated interchangeable numbers, which facilitates compatibility verification in service catalogs and parts selection systems.

Benefits of Using an Original Door Module

Using an original module in the rear left door offers several practical benefits:

• maintaining the factory operating logic for comfort systems and door control,
• proper cooperation with other body control units,
• easier diagnostics using service testers designed for Mercedes vehicles,
• reducing the risk of communication errors within the vehicle network.

Consequently, the module provides a technically consistent solution for repairs or replacement of a damaged control unit in the rear left door.

Part Condition and Installation Aspects

The offered component is in used condition, allowing for an economical restoration of system functionality while maintaining the original manufacturer's specifications. Before installation, it is recommended to perform a standard check of the vehicle's electrical system and verify correct selection against the OEM number and interchangeable numbers.

The module is designed for installation in its designated location in the rear left door, utilizing factory connectors and mountings. In many cases, after installation, adaptation or coding using an appropriate diagnostic tester is required for the control unit to be correctly recognized by the vehicle's other systems.

More About the Role of Original Modules in Modern Cars

Modern vehicles, such as the Mercedes W205, C253, or W257, rely heavily on an extensive network of body control units. Selecting the correct, original components directly impacts the stability of comfort and safety systems. If you are interested in how used electronic components help maintain the character and parameters of premium cars, it is worth reading the article: how original used modules and components help maintain the factory DNA of premium brands.

If you are also looking for other components from the category of body control units and electronics, check out our category: Electronic Control Modules and Controllers for Modern Cars, where you will find a wide selection of compatible parts for various models.