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Estimates last updated January 28, 2026

BMW 850CSi Door Lock Actuator Replacement Cost

The average cost for a BMW 850CSi Door Lock Actuator Replacement is between $263 and $314.

Labor costs are estimated between $110 and $161 while parts are typically priced around $153.

This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.

For a more accurate estimate based on your location, use our Fair Price Estimator below.

Door Lock Actuator Replacement

What is a power door lock actuator?

Vehicles equipped with power door locks have a power door lock actuator in each door. The door lock actuator is an electronically controlled motor that automatically locks, or unlocks a door, trunk or rear hatch when the driver or passenger pushes a lock/unlock button on any door panel or remote.

How does the power door lock actuator work?

Door lock actuators are most commonly electric motors that control a mechanical linkage operating the door locks. In some vehicles they used a system of vacuum motors, hoses and actuators to operate the lock mechanisms. No matter which system your vehicle has there will be a small computer that operates the actuators. The computer will receive signals to lock or unlock a door from the key remote fob, the key lock in the car door, a button on the dash or door panel, or in some case from a remote unlocking signal from OnStar or similar services.

When this part fails, you may experience doors that will not lock and/or unlock properly. You may also experience interior lights that stay on when the door is closed and alarm systems that malfunction. Before they completely fail, you may hear a groaning noise from the door as the lock is operating.

What are the symptoms related to a bad power door lock actuator?

When the door lock actuator fails you may experience doors that will not lock or unlock properly. The actuator can incorporate a door switch so you may also experience interior lights that stay on when the door is closed and security & alarm systems that malfunction. Before they completely fail, you may hear a groaning noise or other noises from the door as the lock is operating. In some cases, the door lock actuators will continuously cycle, draining the battery.

BMW 850CSi Door Lock Actuator Replacement Cost by Year

The average cost for a BMW 850CSi Door Lock Actuator Replacement is between $263 and $314 but can vary from car to car.

BMW Door Lock Actuator Replacement Cost Estimates

The average cost for a Door Lock Actuator Replacement is between $263 and $314 but can vary from car to car.

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BMW 850CSi Door Lock Actuator Replacement Cost by Year

The average cost for a BMW 850CSi Door Lock Actuator Replacement is between $263 and $314 but can vary from car to car.

Door Lock Actuator Replacement

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What is a power door lock actuator?

How does the power door lock actuator work?

What are the symptoms related to a bad power door lock actuator?

Can I drive with a power door lock actuator problem?

When a door lock actuator stops functioning it will not have any negative effect on how your vehicle drives, it is safe to drive. However there are a few precautions that should be taken. When driving your car, you will have to manually lock the door with the malfunctioning actuator to avoid the door opening in case the vehicle is in an accident. Also when you park your car you will want to manually lock the door to ensure your items in the vehicle are secure.

How often do power door lock actuators need to be replaced?

The door lock actuators are a mechanical part that operates every time you lock and unlock the vehicle, so they get used frequently. Due to this frequent use, failure of this item is not uncommon. On some vehicles it's common to have one or more replaced while the car is still under warranty, which can be less than five years old. On other vehicles they can go over 100,000 miles. So it just depends on how much you use the car and what car you drive.

How are power door lock actuator issues diagnosed?

When you have an electronically-controlled door lock actuator that isn't working, the mechanic will need to remove the door panel to verify that it is receiving the appropriate electronic signals to operate the lock motor. If the signals are ok, then the part will need to be replaced. If the signals are not ok, then the issue is with the system that controls the actuator. The mechanic will need to perform an electrical circuit diagnosis to determine why the signal is not reaching the actuator.

Failure to eliminate the door lock electrical circuit and the lock mechanism as a source of the problem may result in the replacement of a fully functional door lock actuator.

How is a power door lock actuator replaced?

To replace this part the mechanic will need to remove the door panel to access the lock actuator mechanism. On some vehicles removal of the window and regulator may be required. If the part is operating a trunk lid or rear hatch on a wagon, the inner panel will need to be removed and the part replaced. When replacing the part it may need to be disconnected from the door lock linkage and electrical wiring, then the new part is reconnected to these items. Once the repair is completed, a thorough performance check of the locking system should be performed to verify a completed repair. This check should include the interior lighting, security system, door windows and any other items attached to the door panel that was removed.

What to look out for when dealing with power door lock actuator issues

The diagnosis and replacement of the door lock actuator is a fairly straight forward job for an experienced mechanic, so as a consumer it's important that the part is properly diagnosed and replaced. When you get the car returned after the repair, double check that the door panel is secured and fitting correctly. Also make sure all the door locks, interior lights and security system are functioning properly before you leave. If anything is not working be sure to inform the repair shop before you take your car.