Fuse Box Mercedes W204 W212 Front Relay Control Unit Module SAM A2129003814

The Mercedes W204 W212 SAM Module is an original part from the fuses and fuse boxes category, designed for the front electrical system of the vehicle. It ensures organized circuit management, stable power distribution, and control over key consumers in Mercedes W204 and W212 class cars. This is a solution for users who expect a proven design and predictable electrical system performance.

Specifications and technical data

• SKU: A2129003814
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2129003814
• Substitutable numbers: A2129003814, A 212 900 38 14, A2129015504, A 212 901 55 04, A2129020706, A 212 902 07 06, A2129020806, A 212 902 0806, KD
• Location on the vehicle: Front
• Category: Fuses & Fuse Boxes

Purpose and Function of the SAM Module

The SAM Module for Mercedes W204/W212 acts as a central point for power management and circuit protection in the front part of the vehicle. It is responsible for the logical arrangement of fuses and relays, which facilitates the diagnosis and servicing of the electrical system. By integrating multiple functions into a single component, the number of connections and potential failure points is reduced.

Its placement in the front of the vehicle allows for direct connection to main consumers such as lighting, powertrain components, and comfort equipment. This architecture promotes stable system operation and facilitates service access.

Construction and Design Advantages

The module belongs to the Fuses and Fuse Boxes category, meaning it combines circuit protection with power distribution functions. The OEM construction is designed for specific Mercedes models, ensuring:

• matched mounting geometry to factory points in the body,
• thoughtful routing of current paths,
• optimized placement of fuse and relay sockets.

This solution translates to an organized installation, easier fault localization, and a reduced risk of installation errors.

Benefits of Using an Original SAM Module

Using an original module in a Mercedes W204/W212 maintains the integrity of the entire electrical system. In practice, this means:

• compatibility with the factory wiring harness and vehicle connectors,
• adherence to manufacturer-specified circuit load parameters,
• stable cooperation with other control units and modules in the car.

An additional advantage is the presence of dedicated replacement part numbers, which simplifies selecting the correct variant for a specific car configuration without the need for installation modifications.

Condition, Installation, and Service Application

The offered module is from the group of used OEM parts, making it an attractive service solution for electrical system repairs. It is particularly useful in situations where the existing fuse box has suffered mechanical damage or there are power supply issues to specific circuits.

Its placement in the front of the vehicle allows for relatively simple installation access. When replacing, it is recommended to:

• disconnect the vehicle's power supply before disassembly,
• check the condition of connectors and wiring harnesses for corrosion and overheating,
• transfer the fuse configuration according to the service documentation for the specific vehicle.

Extended Offer and Additional Materials

If you are looking for other Mercedes fuses and fuse boxes, check out our dedicated category: Mercedes fuses and fuse boxes. There you will find a wide selection of parts suitable for various models of this brand.

For drivers interested in improving ergonomics and driving experience, we also recommend our guide article on replacing the steering wheel with a sport or premium version: personalization and ergonomics – when is it worth replacing the steering wheel with a premium model. This is a practical addition to your knowledge for a comprehensive interior upgrade of your vehicle.