Mercedes W212 Fuse Box Rear SAM Relay Control Unit Module A2129003922

Mercedes W212 Fuse Box Rear SAM Relay Control Unit Module is an advanced electrical system component designed for installation in the rear of the vehicle. It is responsible for organized power distribution and circuit protection, which ensures the stable operation of comfort and safety systems. Thanks to a design compliant with Mercedes factory standards, the module ensures a proper fit for wiring harnesses and mounting points in the bodywork.

Specifications and technical data

• SKU: A2129003922-1
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2129003922
• Substitutable numbers: A2129003922, A 212 900 39 22
• Location on the vehicle: Rear
• Category: Fuses & Fuse Boxes

Purpose and function of the SAM module

The described module belongs to the Fuses and fuse boxes category and serves as the central point for electrical protection in the rear area of the vehicle. It integrates fuse sockets and control electronics into a single housing, which facilitates diagnostics and system maintenance. Its location in the rear of the vehicle allows for optimal routing of wiring harnesses to components such as lighting, comfort systems, or additional control modules.

Construction and fitment for Mercedes W212

Mercedes W212 Fuse Box Rear SAM Relay Control Unit Module has been designed specifically for the electrical architecture of this generation. The housing is intended for installation in the rear of the vehicle, with connectors appropriately positioned for factory wiring harnesses. The layout of fuse sockets and connectors is consistent with the factory configuration, which facilitates the transfer of the existing installation without the need for modifications.

As an original Mercedes component, the module maintains compatibility with the manufacturer's diagnostic systems, allowing for correct reading of errors and operating parameters. This makes it the right choice for repairs where consistency with factory service documentation is essential.

Performance characteristics and benefits of use

As an element from the Fuses and fuse boxes category, the SAM module is responsible for:

• protecting electrical circuits through appropriately selected fuses,
• organized power distribution to individual consumers in the rear of the vehicle,
• integrating control functions in one easily accessible location,
• facilitating diagnostics through the centralization of connections.

Such a solution reduces the risk of incorrect connections and shortens the time required for potential repairs and inspections. Using an original module allows for maintaining the operating parameters of the installation as intended by the manufacturer, which is particularly important in vehicles equipped with extensive comfort systems.

Condition, installation, and service application

The offered item is in used condition, making it a reasonable choice for economical repairs when the priority is to maintain the original design at optimal costs. The module is intended for installation in the rear of the vehicle, in the location factory-designated for the fuse box in the W212 model.

In service practice, such a module is most often used in cases of damage resulting from electrical overloads, flooding, or mechanical damage to the housing. Replacing it with an original component allows for restoring proper circuit power supply without interfering with the factory wiring harness.

Support with selection and additional information

When selecting a SAM module for a specific body version and equipment level, it is important to verify compatibility with the manufacturer's markings and the vehicle's electrical configuration. If necessary, it is worth consulting service documentation or an automotive electrician to ensure full compatibility with the existing installation.

If you are planning a comprehensive repair or upgrade of the rear electrical zone in your Mercedes and need other components from the same group, such as additional boxes, distribution modules, or housings with sockets, check the available parts in the Mercedes Fuses and fuse boxes category.

To better plan your purchases and combine various installation elements in one place – from main modules to small components – it is worth reading the guide on completing used parts, available in the article Comprehensive supply: how to complete used car parts in one place.