2015 Mercedes-Benz C200 problems

Filed Oct 15, 2026 · PA

I am filing a formal safety complaint regarding my 2015 Mercedes-Benz C300 (W205), with approximately 65,000 miles. An authorized Mercedes-Benz dealership diagnosed severe corrosion and perforation of the rear subframe and declared the vehicle undrivable due to this condition. The estimated repair cost is $5,531.53. The rear subframe is a critical structural component supporting the rear suspension. Its deterioration may compromise vehicle stability and potentially result in loss of control. I am extremely concerned that such a serious structural failure has occurred at relatively low mileage. Mercedes-Benz has extended rear subframe corrosion warranty coverage to 20 years with unlimited mileage for certain earlier C-Class models, but the W205 is excluded despite experiencing a similar problem. Mercedes-Benz USA denied my request for goodwill assistance. I respectfully request that the federal safety agency investigate whether premature rear subframe corrosion and perforation represent a broader safety defect affecting the W205 platform and whether a safety recall is warranted. The dealership’s diagnosis, repair estimate, and manufacturer correspondence are available upon request.

Filed Oct 13, 2026 · Electrical · TN · fire

To Mercedes-Benz USA Customer Care, I am requesting a formal review and written explanation concerning case #24524936 and the approximately $6,000+ starter-wiring repair on my vehicle. Mercedes-Benz’s August 2017 recall notice for campaign 2017080002, the federal safety agency recall 17V114, states that the starting-current limiter can overheat under specified conditions, potentially causing surrounding components to melt and creating a fire risk. The notice further states that the authorized dealer will install an additional fuse in the electrical line to the starter at no charge. Because my vehicle has experienced burnt starter wiring, I request that Mercedes-Benz provide: 1. Written confirmation of whether my vehicle’s VIN was included in this recall. 2. The date and documentation of any recall remedy performed on my vehicle. 3. The technical findings supporting the determination that my starter-wiring damage is unrelated to the recall. 4. Confirmation of whether the starting-current limiter, additional fuse, and surrounding wiring were inspected. 5. A review of reimbursement eligibility and goodwill assistance for the repair expense. Please escalate this matter for technical review and provide a written response explaining the basis for the denial. If the matter cannot be resolved, I will consider submitting a vehicle-safety complaint to the federal safety agency. Existing case number: 24524936 Mercedes-Benz recall: 2017080002 the federal safety agency recall: 17V114

Filed Sep 2, 2026 · FL

I am reporting a potential safety defect involving the locking/key-detection system in my 2015 Mercedes-Benz C300. On [XXX], at approximately [XXX] p.m. in Coral Ridge, Fort Lauderdale, I secured my young son in his car seat. My purse, containing the key fob, and my phone were on the front passenger seat. I closed the door and walked around to the driver's side. The vehicle had locked all doors by itself. I did not press the lock button or intentionally lock the vehicle. There were no warning lights, messages, alerts, or other symptoms beforehand. My [XXX] son was trapped inside the locked vehicle, and both my key and phone were also inside, leaving me unable to access him or call for help. I flagged down a passing car, and we ultimately had to break a window to reach him. The vehicle has not been inspected by Mercedes-Benz, a dealer, police, insurance, or an independent service center, and the issue has not been reproduced or confirmed. After replacing the window, I have not attempted to recreate the incident because of the safety risk. The vehicle remains available for inspection upon request. I am concerned that the vehicle can lock with the key fob inside the passenger side, creating a potentially serious risk if a child or vulnerable occupant is trapped inside, particularly in hot weather or where immediate assistance is unavailable. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 28, 2026 · Suspension · VA

I am a mechanic speaking on the behalf of a customer; this customer is experiencing problems with her rear subframe. The older generation of her car has a famous issue with rear subframe rusting out. Her car uses an updated part number that is almost identical in construction to the failure prone part that was famous for rusting out, although they are NOT the same number. The failure prone number is 2123503805 or 2043500141, they are installed on the older chassis, w204, w212, etc. The part that is in THIS vehicle is 2123503605, the construction is almost identical to the part numbers listed for the w212 and w204 provided above. There is no drainage holes provided for water that has entered through rain or any other detritus that will permeate on the road's surfaces through natural progression of the vehicle's life, like on the older chassis. The material used is steel with paint on the outside instead of some sort of encapsulation that coats both inside and outside surfaces. And because these don't have any sort of ability to evacuate any substances, they are interacting with unprotected metal and will react into rust. This failure can lead to misalignment at the very minimum of problems, at the worst, it can cause control arms falling off, causing wheel hub assemblies to fall off, this shouldn't have to be explained but this can cause major injury or death, not only to the passengers to the vehicle, but to others who share the misfortune of being at the wrong place at the wrong time. And, the understanding of these not being the SAME part shouldn't warrant the extension of the recall to these particular vehicles, but the failures are similar to what was seen before on other older vehicles and should warrant further investigation. With hope, this could just be an isolated incident, but since patterns are uncanny, this should be investigated with some interest to the public wellbeing. Cordially Naseam F. Samaan Licensed Virginia State Inspector. Sanko Auto Care

Filed Aug 24, 2026 · MD

Vehicle rear subframe has rusted through, causing vehicle to swerve upon braking, making the car unsafe to drive for the occupant, other vehicles on the road, and pedestrians. Mercedes dealer has advised that subframe has rusted through, requires replacement. The car will be brought to the dealer for repair (at owner's expense) by Friday, 8/28/2026. We can request that the dealer provide us with the subframe - please advise. The vehicle provided no warning indications.

Filed Aug 19, 2026 · Suspension · IL

An inspection of my vehicle on August 6, 2026 disclosed that the rear subframe has corrosion, including perforation. It is my understanding that this problem has been identified in mine and many other Mercedes-Benz models, and that Mercedes-Benz has offered an extended warranty to replace the subframe in certain of these models, but my model for the year it was manufactured was not included. I was not made aware of this potential problem by Mercedes-Benz, and they are not offering an extended warranty to resolve this serious safety issue.

Filed Aug 4, 2026 · Suspension · VA

During a mandatory Virginia State Safety Inspection, the vehicle failed due to severe structural corrosion and perforation of the rear subframe. Because these components notoriously corrode from the inside out, the fact that the rust is externally visible and structurally failing indicates an advanced, catastrophic material breakdown.The rear subframe serves as the foundational load-bearing anchor for the rear suspension and control arms. This level of structural rot poses an immediate, severe safety hazard. Had the failure occurred while driving at highway speeds rather than being caught during an inspection, the suspension mounts could have catastrophically detached, causing a sudden loss of vehicle control, unpredictable fishtailing, and an imminent crash risk. There are absolutely no dashboard warning lights, diagnostic trouble codes (DTCs), or driving indicators to alert the driver of this structural degradation. The defect remains entirely hidden until the metal physically fractures or the vehicle fails a professional inspection. Furthermore, because neighboring states (such as Maryland) do not mandate annual safety inspections, this severe structural failure will go entirely unnoticed by thousands of drivers until a catastrophic on-road failure occurs. Mercedes-Benz has already explicitly acknowledged this exact engineering and material defect in the preceding W204 generation (C-Class models up to 2015), subsequently issuing a 20-year, unlimited-mileage extended warranty for rear subframe corrosion. However, Mercedes-Benz has arbitrarily excluded my 2015 W205 C-Class model from this coverage, despite the vehicle employing a highly similar subframe design that suffers from the exact same moisture-trapping and premature rotting failure mechanism. This represents an unaddressed, systemic manufacturing defect that poses an immediate risk to public safety. I’ve included two photos showing holes in the subframe from rusting inside out.

Filed Jul 13, 2026 · Body · CT

Car was pulling to one side. Replaced the front routers and breaks. Problem still persisted. After more investigating the subframe was found to be rusting out, Mercedes of New London CT said it was unsafe to drive. But allowed my daughter to drive it home. This car was purchased it brand new from Mercedes=Benz of Warwick. The car was garaged all it life. This should not happen. They have had recalls and problems with this model just not this one. My concern is the safety of those driving this model clearly the problem was not solved. Please make Mercedes notify people driving this model, that there is a known subframe corrosion issue.

Filed Jun 3, 2026 · Body · VA

My 2015 C300 W205 failed at its state inspection today due to a rusted through rear subframe. I understand that the W204 warranty on this was extended to 20 years/unlimited miles but the W205 was not. I have contacted Mercedes customer care for a potential goodwill repair since this seems to be a known issue with class actions pending. This should not be failing and it’s unclear why Mercedes did not include all models with the same design in its extended warranty. The costs could be up to $7k.

Filed May 17, 2026 · Suspension · OH

The car would seem to shift when stopping , when tires were removed the rear subframe had rusted out completely, this is a major safety issue and could cause loss of control of the vehicle. The failure is the same as what the w204s experienced but they’re being fixed at the cost of Mercedes