Mercedes Door Lock

Symptoms of Vacuum Door Lock Failure in Mercedes


By Bavarian Performance Specialists March 2, 2018

Owning a vehicle comes with its drawbacks and perks, no matter what kind of vehicle you drive. However, many of us expect that owning a luxury vehicle counteracts most of the drawbacks the typical car owner might face. Unfortunately, this simply isn’t the case. Luxury vehicles, like Mercedes, tend to come with their own set of unique issues that must be addressed by a Mercedes specialist. Many dealerships and automotive shops take advantage of client misconceptions, leading to heightened repair costs and extensively time-consuming automotive work. Luckily, not all shops operate this way.

One of the common issues that are present in a range of Mercedes vehicles is problems with the vacuum door locks. Vacuum door locks were invented decades ago, and remain a part of many vehicle designs today. However, if you have never faced issues with vacuum door locks, they can be tricky to diagnose and fix. It’s critical to bring your Mercedes to a shop with specialized knowledge of how certain Mercedes models’ door locks work so that the problem can be properly assessed and solved. If you’re having issues with your Mercedes’ door locks, here are some symptoms to be aware of and what could be causing them.

Symptoms of vacuum door lock failure

Usually when vacuum door locks begin to fail, they fail systematically. In other words, it’s rare that all of the doors in your car will be unable to lock, but it’s typical for one door at a time to begin experiencing problems. If your locks aren’t working on your Mercedes, it can be extremely inefficient, problematic, and inconvenient, which defeats the purpose of owning a luxury vehicle in the first place. If you notice that you’re having difficulty locking one or more of your Mercedes’ doors, the problem could be traced back to one or more components of the vacuum door locking system.

Potential causes of failure

As we mentioned, there could be several components of the vacuum door lock system that are malfunctioning or beginning to wear. It’s important to remain vigilant of door locking issues, as it’s not safe to leave your Mercedes unlocked when left unattended. Diagnosing the problem begins with isolating the exact source of the issue, or the exact part of the vacuum door locking system that needs repair or attention.

Leaking actuators

Every door lock in your vehicle operates with an actuator. When they fail, it can lead to problems locking one or more door. Depending on what type of Mercedes you drive, the actuators will work differently and require different attention. For instance, some Mercedes’ actuators are equipped with rubber diaphragms that can generally be replaced easily and inexpensively. However, sometimes it’s simply more effective to replace the actuators themselves.

Vacuum pump failure

On most Mercedes models utilizing vacuum locking systems, the vacuum pump is located beneath the front passenger side of the vehicle. The point of this pump is to suck in and blow out air that controls the door locking mechanism. If the pump begins to fail, it can directly impair the ability for the doors to lock. When taken to a Mercedes specialist, this issue can be relatively easily-isolated.

Overall aging system

Vacuum door locking systems have been used in many Mercedes models for many years. Because of this, it is typical for older Mercedes models to run into issues with the various system components. As the vehicle ages, so do the door locking parts such as the various air lines that control the door locking mechanism. When these lines begin to deteriorate, it can cause the mechanism to lose power and malfunction.

How to address vacuum door lock failure

Mercedes-Benz C117 CLA200 The most important first step in addressing your Mercedes’ door lock failure is to bring it to a Mercedes specialist in your area. If you are a resident of Thousand Oaks, Agoura Hills, Westlake, Malibu, and Newbury Park, CA, then Bavarian Performance Specialists is the right shop for you. Our expertise is in European imports—particularly Mercedes vehicles—and we strive to uphold the strict standards that Mercedes cars are formed upon. If you’ve encountered issues with your car’s door locking system, it’s critical for your vehicle’s safety and integrity to bring it in for an inspection at the very least. Please contact our shop to speak to one of our professionals and schedule an appointment as soon as possible.

Mercedes-Benz C117 CLA200 image credit goes to: DarthArt.