Mercedes CLA C117 WIndow Lifter Rear Left N/S Window Regulator A1177300179

Mercedes CLA C117 WIndow Lifter Rear Left N/S Window Regulator is a factory-original component of the rear door window lifting system on the driver's side, designed for Mercedes CLA C117 generation models. A used window regulator from this series allows for the restoration of the proper operation of the window mechanism, ensuring stable window guidance and correct integration with the factory electric controls. By maintaining the original design, this solution is technically consistent with the vehicle's factory specifications.

Specifications and technical data

• SKU: A1177300179
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A1177300179
• Substitutable numbers: A1177300179, A 117 730 01 79
• Location on the vehicle: Rear, Left
• Category: Window Motors & Regulators

Purpose and function in the window system

The rear left window regulator in the Mercedes CLA C117 is responsible for precise guidance and stable positioning of the window in the rear left door. The component works with the electric window control system, enabling smooth opening and closing of the window from the driver's panel or the button in the rear passenger door. A properly selected regulator reduces the risk of jamming, play, and uneven window movement.

The placement on the vehicle in the rear, left part of the body ensures that the component is matched to the door geometry and guides intended for this side of the vehicle. Using the correct part is important for door sealing, proper window pressure against the seals, and acoustic comfort inside the cabin.

Design and fitment for Mercedes CLA C117

The window regulator belongs to the Window regulators and motors group, which means it is designed to work with the electric window drive in Mercedes vehicles. The original design ensures compatibility with factory mounting points in the door, the correct length and routing of cables, and the appropriate gear ratio of the mechanism relative to the weight of the window.

In practice, this translates into:

• proper fitment with the door sheet metal and window guides,
• compatibility with the factory window motor,
• maintenance of the window travel range intended by the manufacturer,
• reduction of stress in the mechanism during operation at extreme positions.

As a result, installation in the Mercedes CLA C117 does not require structural modifications or mounting adaptations, which is essential for durability and operational safety.

Characteristics of the used component

The rear left window regulator offered as a used original part is a beneficial solution for users looking for parts with factory geometry and fitment, while optimizing repair costs. Unlike aftermarket replacements with uncertain specifications, the original regulator retains the parameters intended by the vehicle manufacturer, which is crucial for the operation of the entire window system.

Choosing a used window regulator is particularly justified in the case of maintenance repairs, where the cable mechanism or window guidance has failed, while other door components remain functional. Using a part from the same design group allows for reducing the risk of recurring faults resulting from inaccurate fitment.

Benefits of using an original window regulator

Using a window regulator dedicated to the Mercedes CLA C117 on the rear left side provides a number of practical benefits:

• Consistency with the factory electrical system – correct cooperation with control modules and cabin buttons.
• Proper guide geometry – reduction of noise during window operation and minimization of the risk of misalignment.
• Predictable mechanism behavior – in line with the vehicle manufacturer's assumptions.
• Ability to restore full functionality of the rear window without interfering with the door structure.

For users who want to keep their vehicle in a configuration close to the factory state, choosing such a component is a technically sound solution.

If you are planning a comprehensive repair or upgrade of the side window area in your Mercedes and need other components from the same group, such as lifting mechanisms, electric drives, or guides, check the available parts in the Mercedes Window regulators and motors category.

Additional technical support and knowledge

When planning broader service work on the car, it is also worth considering the condition of the engine unit and the potential costs of its maintenance. For comparison with other brands and a better understanding of how engine failures can affect your operating budget, the following guide material may be helpful: BMW E90 problematic engines: check what can ruin your budget!. Although it concerns a different manufacturer, it shows how important a conscious approach to part selection and repair planning is for the entire vehicle.