Mercedes W221 Door Lock Latch Mechanism Actuator Front Left N/S A2217207935

Left front door lock for Mercedes W221 is an original locking mechanism with a built-in actuator, designed for installation on the driver's side. This component belongs to the Locks and Latches category and ensures the proper, stable operation of the central locking system and secure closing of the doors in the W221 S-Class body.

Specifications and technical data

• SKU: rhd-A2217207935
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2217207935
• Substitutable numbers: A2217207935, A 221 720 79 35, KD
• Location on the vehicle: Front, Left
• Category: Exterior Locks & Lock Hardware

Vehicle Application and Placement

The presented lock mechanism is designed for installation on the front left door of Mercedes S-Class W221 models. Its placement in the vehicle is factory-defined, allowing the lock to work with original guides, linkages, and the electrical system responsible for locking control.

Precise fitting to the specific side of the body reduces the risk of play, leaks, and improper operation of the external and internal door handles. This solution is particularly important in luxury vehicles where door operation comfort and mechanism repeatability are of significant practical value.

Lock Mechanism Construction and Function

The mechanism combines a mechanical part responsible for locking and an electric actuator controlled by the central locking system within a single housing. The assembly works with the vehicle's factory electronics, enabling:

• automatic locking and unlocking of doors via remote control or an in-cabin button,
• proper cooperation with the lock cylinder and door handles,
• stable holding of the doors in the closed position while driving.

The original design ensures the correct geometry of latches and levers, resulting in a repeatable handle stroke and proper door closing without the need for additional adjustment of hinges or the striker plate.

Benefits of Using an Original Mercedes Lock

Using a factory lock for the Mercedes W221 maintains the integrity of the body and electronics system. Key benefits include:

• Compatibility with Vehicle's Electrical System – electrical connectors and mounting points match factory standards, facilitating installation.
• Appropriate actuator performance – the lock responds according to the control logic used in the W221 comfort system.
• Proper fit with door sheet metal and guides – reduces noise, vibrations, and unwanted play during operation.

Therefore, replacing a worn or damaged part with an original lock from the same series restores the correct operation of the central locking system without interfering with the wiring harness or requiring additional mechanical modifications.

Condition and Service Application

The offered left front door lock is a used part, providing a cost-effective service solution for Mercedes W221 owners seeking parts within a reasonable budget while maintaining original specifications. This type of component is suitable for both typical central locking repairs and for replacing a mechanism after wear-and-tear damage or collision damage.

In workshop practice, installing an original used lock can reduce repair time, as the part is a complete assembly with an actuator and locking mechanism, ready for installation in the driver's side door.

Related Products and Technical Knowledge

If you are planning comprehensive service for your Mercedes S-Class's locking system and are also interested in other parts from the locks and latches category dedicated to this brand, check out the available parts in the Mercedes Locks and Latches category.

For users who are simultaneously servicing the powertrain and want to better understand the relationship between gearbox operation and vehicle driving comfort, a guide describing common faults and selecting used transmissions may be helpful – detailed information can be found in the article Gearbox: Manual, Automatic, or DSG – Common Faults and a Guide to Buying a Used Gearbox.