Mercedes Benz Parts Repair 101: Diagnostics for Air Suspension
Mercedes Benz, both new and pre-owned, are popular with US consumers, with 191,463 new vehicles and 75,192 pre-owned sold in 2019 alone.
If you're one of the many Mercedes Benz car owners keen to keeping their vehicle in top running condition, you already know your car’s air suspension system is unique.
It doesn't matter whether it’s an E-Class, S-Class, R-Class, CLS-Class, or CL-Class, Mercedes Benz parts differ from traditional steel suspension spring designs. The air suspension system used is called an Airmatic system.
But what happens when the Airmatic air suspension fails?
Let’s take a look. But first:
Mercedes Benz Air Suspension: An Overview
The Airmatic system on Mercedes Benz cars is controlled by an Air Suspension Control Unit or N51. This type of suspension allows the driver to choose their driving modes, such as Comfort or Sport.
The suspension can be adjusted depending upon road conditions and a person’s driving habits. The vehicle level is monitored, depending on what speed you’re driving.
So, suppose you go over 40mph. In that case, your car lowers so that the center of gravity allows you to better handle the vehicle and reduce the risk of rollover or dragging.
Mercedes Benz Parts: The Benefits of an Airmatic Suspension
The main benefit is that this type of suspension in your Mercedes Benz absorbs the shock your car experiences on different types of roads. This includes any potholes or bumpy and uneven roads. Your Airmatic suspension keeps you steady on the road.
The Airmatic system also ensures that your car is safe in the event of hitting large potholes and bumps in the road. The centrifugal force pushes the car in an outward direction, lowering the vehicle to ensure the car’s wheels always contact the road.
Why Does the Airmatic System Fail?
Some of the most common reasons for Mercedes Benz parts failure include:
Air Strut Leakage: Like all Mercedes Benz parts and other car parts, air struts suffer wear and tear over time. If this happens to your air struts, they may begin to leak. Your car will drop to one side or corner where the leak is.
Air Suspension Compressor Malfunction: This is the part that’s responsible for producing compressed air. If it stops working, little or no air is directed, causing low pressure, which in turn causes your air suspension system to fail.
A Blown Fuse: Your Mercedes Benz fuse is what makes your Airmatic system work. If this blows, your air suspension will fail.
Airbags Leak: If there's a leak in the suspension airbags, your air compressor will keep running continuously because it’s trying to maintain the right amount of air pressure. This means you might still hear the compressor even when you’ve turned your engine off.
Valve Failure: When your Airmatic valves fail, you’ll see “Air Suspension Failure” pop up on your dashboard. You may also see a “Stop, Vehicle Too Low” message.
Mercedes Benz Parts: What To Do
First, if you see air suspension failure messages on your dashboard, it’s important not to panic.
Your best bet in the short and long term is taking your car to a specialist workshop where Mercedes Benz enthusiasts can help diagnose and deal with the problem.
Alternatively, you can contact a Mercedes Benz parts specialist who can advise you on the best course of action. However, if you’re not an absolute beginner, there are a few troubleshooting steps you can follow.
Let’s take a look:
Air Strut Leakage or Failure
If your car is dipping or leaning to one side, you can check if you have an air strut leak or failure by spraying a mix of soap and water on the mastic. This is located at the top of your air strut.
If you see bubbles forming, you’ll know where your leak is coming from, and you can then either replace or repair your air strut.
Air Suspension Compressor Failure
If your air suspension compressor has failed, your car will lower and not rise. Press your “raise” button. If nothing happens, check your air compressor voltage and if there is any power.
If the voltage is low, check your fuse and your relay. You can also use an OBD-II scanner to view any faults in your air suspension control unit. If there are any fault codes, reset them. If this doesn’t work, replace your air suspension compressor.
Blown Fuse
If you suspect your air compressor fuse has blown, take a look at the Airmatic relay.
This is found in the engine compartments' main fuel box. Check the fuse for the air suspension compressor. If you find that your fuse is often blowing, you’ll need to buy and install a new relay.
Airbags Leak
If you’re hearing your compressor after your engine is off, it may be time to replace your airbags. In some Mercedes Benz, airbags can be replaced with ease if they are at the front of the vehicle, and you don’t need to replace your entire strut either.
In some cases, the airbags are challenging to access without removing your whole exhaust system first. In such a case, we’d advise you to enlist the help of professionals.
Valve Failure
If your valves fail and you’re seeing the messages we referred to earlier jumping in red on your dashboard, you’ll need to heed the warning. Take your Mercedes Benz to a specialist to take a look.
Are You Ready to Handle Your Mercedes Benz Parts Repair?
We hope having read this blog post you feel more educated in the diagnostics for air suspension for your Mercedes Benz.
If you have any questions on the subject, contact UroTuning today. We’re the number one source for Mercedes Benz parts. We're dedicated to providing the best customer service possible, as well as competitive pricing on all the parts we sell.