Mercedes-Benz is one of the most iconic vehicle manufacturers known for their high-quality, luxury and performance. However, they are still susceptible to wear and tear or even design flaws from the factory.
One well-known issue concerns aluminum fuse failure. If said failure occurs, the electrical system in your Mercedes might work intermittently and lead to confusing issues like a sudden inability to activate the windshield wipers when it starts to rain or the defroster on a cold morning. Worst case scenario, you might be unable to start the car at all.
Aluminum is a material that naturally degrades over time, so it’s reasonable to expect fuse failure in an older Mercedes. However, this process is often accelerated due to a design flaw: close proximity of copper to the aluminum fuse.
Copper actually contributes to faster degradation of aluminum through a process known in chemistry as galvanic corrosion. Simply put, for the purposes of understanding why this is a design flaw, the copper and aluminum interact in such a way that the aluminum gives away some of itself to the copper (through electron transfer), ensuring it wears out faster than it would have on its own. To do this, there has to be an electrolyte present, and condensation/moisture is a good candidate; thus, Mercedes models that are stored outside are likely even more susceptible due to experiencing more of the natural elements.
Causes and Symptoms of Aluminum Fuse Failure in Mercedes-Benz
As discussed above in the design flaw section, there are three primary reasons the aluminum fuse could fail:
- Age: Aluminum naturally degrades over time, so if you drive a classic Mercedes, it’s important to keep potential fuse failure in mind.
- Environment: Weather conditions can influence the rate at which aluminum degrades. Consider high humidity and moisture-rich areas that will most likely exacerbate the degradation by facilitating an interaction with the nearby copper. This is also something to remember when buying a used car and you’re unaware of how previous owners stored the vehicle.
- Design flaw: Copper being installed so close to the aluminum fuse speeds up the process of degradation and causes premature fuse failure.
When the fuse is failing, you might notice accessories that rely on the electrical system of your car are unreliable; for example, your radio only works sometimes. You may notice you can’t start the car despite having a good battery.
It is potentially dangerous to drive your Mercedes with fuse failure as you might be unable to use the wipers in a heavy downpour, limiting visibility, or turn on the headlights at night, rendering you nearly invisible to other drivers as well as unable to see the road in front of you on unlit roads. It’s crucial to be able to rely on those systems to work every time to be as safe as you can and also maximize performance. Also, it’s impossible to enjoy a night drive if your headlights go out, and it won’t matter how luxurious the interior is if another vehicle rear ends you because your taillights failed to turn on.
Servicing the electrical system of a vehicle is a job best left to those who are trained to do so, as improper maintenance can be dangerous. Burns or even fires are possible if unsafe methods are used to service an electrical system. If you notice electrical issues with your Mercedes, plan to have it inspected by a qualified shop that is familiar with working on these vehicles.
Hagan’s Motor Pool for Your Mercedes-Benz Aluminum Fuse Replacement
Hagan’s Motor Pool in Rochester, New Hampshire is a full-service dealership specializing 
in German vehicles. Our customers also come from surrounding areas including Alton, Barrington, Berwick, and Dover, NH.
We have modern diagnostic equipment to ensure quick and accurate diagnosis on your car, saving you time and money. All our labor is warrantied for 12 months of 12,000 miles (whichever comes first), and all parts are warrantied by the manufacturer. As a veteran owned business, we also gladly offer discounts to veterans!
We are located at 152 Farmington Road, Rochester, NH 03867 and open from 8:00AM to 5:00PM Monday through Friday. To have your Mercedes-Benz inspected and repaired, contact us to schedule an appointment at (603) 332-6822 or through the form on our website.
* Mercedes-Benz Car image credit goes to: kurmyshov.