The vacuum front right (FR) door lock actuator for the Mercedes-Benz S-Class W221 (2006–2013) is part of the central locking system, which uses vacuum pressure rather than purely electric actuators. Here’s a detailed description:

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Component Name:

Vacuum Door Lock Actuator – Front Right (FR)

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Vehicle Application:

• Model: Mercedes-Benz S-Class
• Chassis: W221
• Years: 2006–2013
• Position: Front Right (Passenger Side – RHD vehicle)

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Function & Operation:

• Operates via the vacuum system (using a central vacuum pump under the rear seat/trunk).
• Controls locking and unlocking of the front passenger door using vacuum pressure.
• Connected to the central locking system and works in sync with remote key or door lock/unlock signals.
• Uses a vacuum line to either lock (pull vacuum) or unlock (release vacuum) the door latch mechanism.

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Construction & Features:

• Integrated plastic housing with vacuum diaphragm.
• Rod or cable connection to the door latch/lock mechanism.
• Usually comes with two vacuum ports: one for lock, one for unlock.
• Sometimes includes built-in position sensor for feedback to the vehicle’s control module (depending on variant).

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Common Issues:

• Vacuum leaks causing slow or non-functioning lock/unlock.
• Sticking actuator due to age or dirt.
• Broken internal diaphragm or plastic parts.
• A failed unit can cause the whole vacuum system to misbehave (e.g., hissing sounds or pump running too long).

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Replacement Notes:

• Must be accessed by removing the door panel.
• Ensure vacuum lines are reconnected correctly (Lock/Unlock ports).
• Some aftermarket or used replacements are available; OE part numbers vary slightly by year/model.

If needed, I can also help find the exact part number or diagram.