Ford Focus Mk3 Window Lifter Motor Regulator Rear Left N/S BM51-A27001-BC

Ford Focus Mk3 Window Lifter Motor Regulator Rear Left N/S is an original component from the Window regulators and motors group, designed for installation in the rear left door of this model. It ensures stable operation of the window lifting and lowering mechanism, which translates into ease of use and proper window closing during daily operation. This solution is dedicated to drivers who want to restore full functionality of the side window without compromising on fitment.

Specifications and technical data

• SKU: BM51-A27001-BC
• Mark: Ford
• Condition: Used
• OEM Part Number: BM51-A27001-BC
• Substitutable numbers: BM51-A27001-BC, BM51A27001BC, 1870372, BM51-A27001-BE
• Location on the vehicle: Rear, Left
• Part type: Window Motor
• Category: Window Motors & Regulators

Purpose and fitment for Ford Focus Mk3

The presented window lifter is designed specifically for the rear left body area of the Ford Focus Mk3, which ensures proper window guidance and correct mounting geometry. Its placement in the rear left door area guarantees compatibility with the factory door and window construction, without the need for modifications or adaptations. Thanks to the use of a solution from the Window regulators and motors group, the component works with the factory window control system, maintaining the performance characteristics intended by the manufacturer – both in terms of movement smoothness and opening range.

Technical and functional characteristics

The window lifter is responsible for transferring power from the control system to the window, ensuring its even guidance in the tracks. The construction is prepared for operation in typical passenger car conditions, taking into account the loads resulting from frequent raising and lowering of the window. Key advantages of this solution include:

• dedicated placement in the rear left door, which facilitates installation and service,
• maintenance of factory window operating geometry, reducing the risk of jamming and misalignment,
• compatibility with the original window control system in the Ford Focus Mk3. A component configured in this way allows for the restoration of proper window operation after the previous mechanism has been damaged, without interfering with the electrical installation or the door structure.

Benefits of using an original Ford component

Using an original Ford solution translates into predictable mechanism behavior over a long period of use. Factory fitment to the door structure minimizes the risk of improper window closing, excessive play, or noise while driving. By choosing this window lifter, you gain:

• consistency with other window system components in the vehicle,
• easier diagnostics during future inspections,
• the ability to maintain the original vehicle specification, which is important for future resale of the car.

Condition and use in repairs

The component comes from the secondary market, which allows for economical repair of the window system while maintaining the original construction. This type of solution is particularly beneficial for post-accident repairs or when replacing a worn-out mechanism, where the priority is combining functionality with reasonable cost. In practice, the window lifter will work well both in the case of a single replacement of a damaged mechanism and during broader service work within the rear door, where compatibility with factory mounting points is essential. If you are planning a comprehensive repair or upgrade of the side window area in your Ford and need other elements from the same group, such as lifting mechanisms, drives, or guides, check the available parts in the Ford window regulators and motors category. To better plan your repair budget and consciously choose components from the secondary market, it is worth learning the principles of selecting used OEM parts and the real cost differences between new and used components – this is discussed in more detail in the guide Why it is worth buying used gearboxes and engines – facts instead of myths, which helps apply these principles to other vehicle components as well.