Mercedes W212 Fuse Box Rear Relay Control Unit Electric Module SAM A2129060605

Mercedes W212 Fuse Box Rear Relay Control Unit Electric Module SAM is an advanced electrical system component responsible for power distribution and control of selected circuits in the rear of the vehicle. This module, designed for installation in the rear body section, allows for efficient management of electrical loads and stable operation of comfort and safety systems. Thanks to its factory origin from the Mercedes range, you maintain compatibility with the vehicle's original electrical architecture.

Specifications and technical data

• SKU: A2129060605-1
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2129060605
• Substitutable numbers: A2129060605, A 212 906 06 05, 5DK011023, 5DK 011 023, A2125452832, A 212 545 28 32, A2129028502, A 212 902 85 02
• Location on the vehicle: Rear
• Category: Fuses & Fuse Boxes

Purpose and function in the vehicle

The described SAM module is a component from the Fuses and fuse boxes category, operating in the rear part of the body. It is responsible for:

• distributing power to consumers located in the rear of the vehicle,
• protecting circuits through appropriately selected fuses,
• integration with the electrical installation and control systems in the Mercedes W212.

Its placement in the rear zone of the vehicle helps shorten wiring harnesses and reduce voltage drops, which translates into more stable operation of electrical systems.

Construction and technical advantages

The rear SAM module in the Mercedes W212 is designed as a compact fuse box integrated with control electronics. This design ensures:

• organized circuit routing and easier diagnostics,
• the ability to quickly replace individual fuses without interfering with the rest of the installation,
• factory fitment to the mounting points and connectors in the W212 body.

By using an original solution, compatibility with factory software and control logic is maintained, which minimizes the risk of communication errors in the vehicle's network.

Condition, origin, and fitment

The presented module comes from the Mercedes offer and is a used component, which allows for an economical yet technically sound repair of the electrical system. In practice, this means:

• preservation of original mounting points and connectors,
• no need for installation modifications when correctly matched to the vehicle version,
• the ability to use the existing wiring harness in the car.

Before installation, it is recommended to verify the module's compatibility with the equipment of the specific W212 unit and to check its correct operation in conjunction with other control units.

Benefits of using an original fuse box

Using a rear SAM module dedicated to the Mercedes W212 brings a number of practical benefits:

• Consistency with the factory installation – the original design works with the existing electrical architecture without the need for adaptation.
• Power stability – properly designed current paths and protections reduce the risk of failures resulting from overloads.
• Easier diagnostics – the module is designed to work with factory service tools, which facilitates fault localization.

For users and workshops, this means faster repair, lower risk of secondary problems, and maintenance of operating parameters close to factory standards.

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

Additional information and technical advice

When replacing the rear SAM module in a Mercedes W212, it is worth paying attention to the correct seating of connectors, the condition of the harnesses, and any potential need for adaptation in the vehicle's diagnostic system. In the case of extensive interior equipment modifications or retrofitting the car with additional electrical consumers, practical tips on cabin ergonomics and comfort, available in the article Car interior tuning with Global Parts, may also be helpful.