Mercedes-Benz Vito W639 Loudspeaker Cable Wiring Loom Harness A6394404906

The MERCEDES Vito W639 Door Harness is an original electrical system component designed for the rear of the body, specifically for Mercedes vehicles. It ensures proper electrical connection of components installed in the rear doors, providing stable communication with the vehicle's main electrical system and correct operation of sub-assemblies.

Specifications and technical data

• SKU: A6394404906
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6394404906
• Substitutable numbers: A6394404906, A 639 440 49 06, EM
• Location on the vehicle: Rear
• Category: Wiring Harnesses, Cables & Connectors

Purpose and Function of the Rear Door Harness

The presented MERCEDES Vito W639 Rear Door Harness belongs to the group of electrical system components responsible for transmitting signals and power between the rear doors and the rest of the vehicle. It ensures safe routing of wires in the area of the moving connection between the body and the door, minimizing the risk of chafing, circuit breaks, and interference with receiver operation.

This solution is particularly important in vehicles used intensively – both in fleet and private applications – where the rear doors are frequently opened and closed, and the harness is subjected to repeated bending.

Construction and Technical Features

The harness falls into the category of Cables, Harnesses, and Connectors, meaning it is designed as a complete connection of wires with appropriately selected connectors and mounting points. The construction includes:

• wire routing that limits mechanical stress during door operation,
• dedicated connectors matched to the rear part of the vehicle's electrical system,
• a wiring layout optimized for the specific Vito W639 generation.

This ensures an organized installation process and reduces the risk of incorrect wire routing.

Benefits of Using an Original Rear Harness

Using an original door harness in a Mercedes Vito W639 maintains the consistency of the electrical system with the vehicle's factory documentation. This translates to:

• more reliable diagnostics – electrical diagrams correspond to the actual wire routing,
• stable operation of receivers located in the rear doors,
• reduced risk of failures due to incorrect connections or makeshift repairs.

A component in used condition is a cost-effective solution while maintaining original construction and fit for the specific body model.

Installation and Application in the Rear of the Vehicle

The placement of the harness in the rear zone of the vehicle requires maintaining the correct wire routing path and proper seating of connectors in the factory mounting points. In practice, this means:

• the need to remove appropriate covers and upholstery from the rear of the body,
• connecting the connectors according to the factory electrical system layout,
• checking the correct operation of receivers after installation is complete.

The harness is designed to operate in the moving connection between the door and the body, so proper wire arrangement is crucial for the durability of the repair.

Complementary Mercedes Electrical System Components

If you are planning a comprehensive repair or upgrade of the rear electrical system zone in your Mercedes and need other components from the same group, such as additional harnesses, cables, or connectors, check the available parts in the Mercedes Cables, Harnesses, and Connectors category.

Additional Information on Using Used Parts

When selecting electrical system components, many users consider using used parts as a way to reduce service costs while maintaining original quality. For more demanding makes and models, it is worth learning about best practices related to this approach – the article Luxury within Reach – How to Service a Porsche Legend Using Proven Used Parts, which describes how to consciously use dismantled components in advanced car constructions, discusses this in more detail.