Volkswagen VW Eos 1F Window Glass Regulator Lifter Rear Left N/S 1Q0839401B

Volkswagen VW Eos 1F Window Glass Regulator Lifter Rear Left N/S 1Q0839401B is an original component from the Window regulators and motors group, designed for precise operation within the side window mechanism of a convertible body. It ensures stable window guidance in the rear part of the vehicle on the driver's side, which is crucial for sealing, acoustic comfort, and proper interaction with the folding roof.

Specifications and technical data

• SKU: 1Q0839401B
• Mark: Volkswagen
• Condition: Used
• OEM Part Number: 1Q0839401B
• Substitutable numbers: 1Q0839401B, 1Q0 839 401 B
• Location on the vehicle: Rear, Left
• Part type: Window Regulator
• Category: Window Motors & Regulators

Purpose and vehicle placement

The presented window regulator is designed for installation in the rear part of the body on the left side, in the passenger side window zone. It is responsible for the controlled movement of the glass within the guides, working in conjunction with other window mechanism components and the vehicle's electrical system.

Thanks to its dedicated fitment for the Eos model design, this component maintains the correct window operating geometry, which reduces the risk of misalignment, excessive play, or improper closing in automatic mode.

Function and benefits of use

A fully functional window lifter in a convertible has a direct impact on:

• proper window closing in comfort mode,
• maintaining a seal between the glass and the folding roof seals,
• reduction of wind noise at higher speeds,
• stable window guidance throughout its full range of motion.

Replacing a worn or damaged mechanism with an original part from the same design group allows for the restoration of the entire window system's proper operation, without the need for bodywork intervention or installation modifications.

Characteristics and technical fitment

The window regulator was developed as a factory part by Volkswagen, which means it maintains compatibility with factory mounting points and the existing window control system. As a result, installation is predictable for an experienced mechanic, and the risk of issues with window position calibration is minimized.

The component belongs to the Window regulators and motors group, which facilitates its identification in service catalogs and selection in relation to other system components, such as guides, seals, or control modules.

Condition and service application

The offered window lifter is a used part, making it an attractive service solution for the repair of daily-driven vehicles, where a reasonable balance of cost and functionality is important. In workshop practice, such components are often used for:

• repairing the window mechanism after operational damage,
• resolving issues with the window getting stuck in one position,
• restoring proper window interaction with the folding roof.

Due to the retention of the original design, the part can be used as a direct replacement for the component factory-installed in the vehicle, without the need for adaptation or modifications.

System expansion and selection of related components

If you are planning a comprehensive repair or upgrade of the side window area in your Volkswagen and need other elements from the same group, such as additional regulators, lifting motors, or related guides, check the available parts in the Volkswagen Window regulators and motors category.

When selecting components for control and drive systems in a vehicle, it is worth using procedures based on manufacturer markings and catalog data. A detailed discussion on how to identify components by factory markings, along with practical examples and an analysis of repair cost-effectiveness, can be found in the guide Why it is worth buying used gearboxes and engines – facts instead of myths, which organizes the most important issues related to the use of used parts in professional service.