2015 Mercedes-Benz C-Class
Problems, recalls and owner-reported issues
Engine is the leading concern among 449 owner complaints filed for this model year. This is the 7th highest complaint count among 23 C-Class model years with reports.
Of the 2015 reports, 11 involved a crash and 1 involved a fire. 10 people were injured.
What owners report most often
Recalls and investigations
No safety recalls on file.
Representative owner complaints: other or unspecified
75 reports, newest first. Show all
Other or unspecified, Sep 23, 2026
The vehicle’s rear subframe has become severely rusted and structurally compromised. This failure has caused the vehicle to pull sharply to the right when the brakes are applied. The rear subframe and affected components are still on the vehicle and are available for inspection upon request. This condition creates a serious safety risk because the vehicle can suddenly pull hard to one side during braking, making it extremely difficult to maintain control. At highway speeds or during emergency braking, this could cause the driver to lose control of the vehicle, leave the roadway, collide with another vehicle or object, or potentially result in a rollover. The failure is especially concerning because it directly affects the stability and braking behavior of the vehicle. The problem was inspected and confirmed by Mercedes-Benz of Durham. The dealer determined that the rear subframe was severely rusted and that this condition was responsible for the vehicle pulling strongly to the right during braking. The vehicle has therefore been inspected by an authorized Mercedes-Benz dealership. The condition has not, to my knowledge, been inspected by police or insurance representatives. There were no warning lights, dashboard messages, or noticeable symptoms indicating that the rear subframe was deteriorating before the problem became apparent. There was no advance warning that the subframe had become severely rusted. The issue only became evident when the vehicle began pulling sharply to the right under braking. Because there were no warning signs before the failure, I believe this condition presents a significant safety hazard. A driver may continue operating the vehicle without knowing that the rear subframe has deteriorated to the point that vehicle stability and braking control are affected.
Other or unspecified, Sep 2, 2026
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)
Other or unspecified, Aug 24, 2026
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.
Other or unspecified, Jul 16, 2026
Sunroof Glass failure vin:55SWF4KB1FU039607 2015 Mercedes C300 2PM July 16 2026, Tampa highway near college park east coordinates28.06840 N.82.35292W TEMPERATURE 91F
Steering, Other or unspecified, Apr 29, 2026
Component/System Failure: The rear subframe on my 2015 Mercedes-Benz C300 failed due to severe corrosion/rusting. The subframe is available for inspection upon request. Safety Risk: This failure created a serious and immediate safety hazard. While driving at highway speeds, the structural integrity of the vehicle was compromised, I had to break and lost control of the vehicle and almost causing a crash. This also posed a danger to other drivers on the road. The condition was severe enough that I believe I narrowly avoided a major accident. Confirmation of Problem: The issue has been confirmed by a Mercedes-Benz dealership service department, who identified the subframe as rusted and structurally compromised. Inspection by Other Parties: The vehicle has been inspected by a Mercedes-Benz dealership. It has not yet been inspected by the manufacturer directly, police, or insurance representatives. Warning Signs Prior to Failure: There were no clear warning lights or dashboard messages indicating this issue prior to the failure. The problem appears to have progressed without visible warning until it became severe. Additional Context / History: Mercedes-Benz has acknowledged subframe corrosion defects in certain vehicles from approximately 2010–2020, but my specific vehicle was not included in the extended warranty coverage. This is the second Mercedes-Benz vehicle I have owned (previously a 2012 model) that has experienced the same subframe failure. I was previously told that this issue had been resolved in newer models, which influenced my decision to purchase this vehicle. Additionally, this vehicle was purchased as a Certified Pre-Owned Mercedes-Benz, which implies it passed a detailed inspection process. Despite this, a major structural component failed. A warranty claim was submitted but denied on the basis of “rust,” even though this appears consistent with a known factory defect.
Other or unspecified, Apr 24, 2026
Mercedes issued a recall for Mercedes C class for the model year up to 2015 for rear subframe that is rusting with holes in it. The dealer tells me my car is not covered by Mercedes even though it is a 2015 model. They gave me an estimate for the repair of over $5000. They say the model changed mid 2015 and mine is a model that is not covered. This could cause a serious crash at high speed. I am not sure why that repair is not covered for my 2015 model & I would like Mercedes to honor the repair.
Other or unspecified, Mar 22, 2026
Rear subframe rotted, hole like perforation on the frame. The current extended warranty covers the C204, but my Mercedes C300 2015 has a C205 that is the same part number, but for some reason the warranty does not cover the C205, but has the same identical issues as the C204.
Other or unspecified, Mar 17, 2026
I am reporting a structural failure of the rear subframe due to corrosion on my 2015 Mercedes-Benz C300 4MATIC. The failure was diagnosed by an authorized Mercedes-Benz dealer, who confirmed that the rear subframe has corroded and broken, compromising the structural integrity of the vehicle. This is not cosmetic rust. The subframe is a load-bearing structural component, and its failure creates a serious safety risk, including potential loss of vehicle control. I have been advised that the vehicle may be unsafe to operate in its current condition. The vehicle has approximately 143,000 miles and has been registered and operated in Connecticut, a salt-use state. However, this level of corrosion leading to structural failure of a major suspension component is premature and not consistent with normal wear and tear, even in such environments. I contacted Mercedes-Benz USA and escalated the matter to an Executive Referral Manager. Mercedes-Benz acknowledged the seriousness of the issue but declined to provide any repair assistance, stating that my vehicle falls outside of warranty extension and goodwill parameters. Mercedes-Benz did not dispute the nature of the failure or its safety implications, but refused to address the issue based solely on internal policy criteria such as age and mileage. A rear subframe supports critical suspension components. Corrosion leading to structural breakage can result in instability, misalignment, or failure of suspension components while driving, increasing the risk of a crash. This issue appears to be consistent with known reports of rear subframe corrosion in similar Mercedes-Benz vehicles, raising concern about a broader safety defect. The failure was identified during inspection, and repair costs are estimated at approximately 5,000–6,000. I am submitting this complaint due to the safety risk posed by structural failure and the manufacturer’s refusal to address the issue.
Suspension, Other or unspecified, Jan 20, 2026
Failed/Malfunctioned Component: Rear subframe (structural/chassis component) exhibited advanced corrosion (perforation/rust-through), compromising structural integrity and alignment/handling. Availability for Inspection: Yes. The vehicle and the subframe are available for inspection upon request. I can provide photos, videos, and repair estimates if needed. The corroded subframe is fracture and detach suspension mounting points, which may lead to: Sudden loss of vehicle stability or control (especially during braking, cornering, or over bumps). Unpredictable alignment changes causing pulling, vibration, or abnormal tire wear that can escalate into a loss-of-control event. Increased stopping distance and potential for wheel misalignment or collapse, raising the risk of a crash involving occupants and other road users. I limited driving/use due to the risk; issue is a structural safety concern rather than cosmetic. Confirmation: Yes on multiple visits since Oct 2023 -Yes—diagnosed and documented by Mercedes-Benz of Silver Spring on Oct 2 2023, Nov 2023 and Dec 2025. Technician confirmed severe corrosion/rust perforation on the rear subframe requiring replacement. No No
Electrical system, Other or unspecified, Engine, Dec 2, 2025
The car suddenly glitched and locked itself—with my dog, my purse, my phone, everything—inside on an extremely hot day. There was no one around, and it was terrifying. I had opened the passenger door for my dog to climb in, and as I walked around to the driver’s side, the doors somehow locked on their own. Panic set in immediately. My dog, my phone, and my purse were all inside, and I had no way to call for help. We had just finished a walk, and then this happened out of nowhere. I had to run around searching for someone who could help. Eventually, I found a stranger who called the police, and they had to break the door open because it was over 100 degrees outside. I was terrified my dog would pass out from the heat. There were no warnings, no alerts, no messages. If it weren’t for that random stranger who happened to be there and willing to help, I don’t know how I would have gotten my dog out. It’s a reminder of the kindness of strangers, but the glitching car was truly terrifying and not ok.
Suspension, Structure, Other or unspecified, Nov 7, 2025
Rear subframe rusted out, car is not safe to drive
Other or unspecified, Sep 16, 2025
I took my 2015 vehicle to the Mercedes dealership and learned the rear subframe is rusted and has holes on two sides. I was warned that it is a safety hazard and could lead to a lack of control and other dangerous situations. I also learned that other 2010 through 2014 Mercedes models in the same class have been recalled for this exact concern. I am disappointed and upset to learn that those concerns are known, but not addressed in this model and put customers at risk.
Suspension, Power train, Other or unspecified, May 29, 2025
Rear-subframe corrosion at the lower-control-arm mounts has progressed to the point where both arms have play and produce loud metallic bangs while braking or turning at low speed. Two independent shops lifted the car, documented flaking rust around the bushing sleeves, and advised the subframe is structurally compromised and could let a control arm detach under load. The corroded subframe remains installed and can be inspected on request. Safety risk: a detached rear control arm would cause sudden, unpredictable steering and loss of control. The vehicle already pulls right under braking, and feels very unstable in curves Problem has been reproduced and photographed by two independent repair facilities. No manufacturer representative has inspected the vehicle so far. Additional component failures possibly linked to the same progressive chassis stress: premature wear of both front CV axles; timing-chain stretch with worn guides; slack oil-pump chain; upper & lower oil-pan gasket leaks; water-pump seepage; right engine-mount collapse; persistent misfire traced to a loose intake-hose clamp; transmission-cooler hose clip released under pressure, dumping all ATF and destroying the automatic transmission; excessive play in all four lower control-arm bushings. The transmission and the other components were replaced 1-2 months before the subframe bro History: A faint clank from the rear suspension first appeared roughly three years into ownership. Dealer service dismissed it as “normal noise,” and warranty would not cover “loud clanks,” so the issue went unaddressed. The noise has grown steadily into the current condition, suggesting long-term subframe corrosion that was never inspected or remediated. No collision, flood, or off-road use; the car has typical Northeast winter-salt exposure. The failure pattern matches subframe-corrosion cases already acknowledged by the manufacturer on this model, although this serial number is not yet included in the official campaign.
Other or unspecified, May 28, 2025
Structure,Body.Roof & Pillars
Other or unspecified, Apr 12, 2025
Sunshade on panoramic sunroof broke off and tore sunshade. Took it to MB service center and was told it is known issue for that model and many more with some part snapping off causing the damage and cost to repair is between 2500-3000. Have been reading online and lot of people seem to have same issue with the panoramic sunroof and shade not syncing together. Seems to be concern manufacturer should be looking at if there’s numerous vehicle with same issues. Part snapped off when trying to open up sunroof on hot summer day
Other or unspecified, Apr 9, 2025
Engine Light- Crankcase Ventilation Valve Replacement P052E71. Vehicle will jolt aggressively at the time of acceleration.
Electrical system, Other or unspecified, Apr 4, 2025
Have noticed a lot of air noise coming from the panoramic sunroof of my vehicle when driving, and now have issues of it opening or closing properly. I researched and found a recall regarding the issues my vehicle is having, and brought it into a dealership for diagnosis. Was told my vehicle VIN was not included in the recall. This is a dangerous issue that needs to be remedied. If the sunroof malfunctions I’m afraid it will come loose from the vehicle as it is doing the same things that the recalled VIN vehicles had issue with. Mercedes needs to update and add additional VINs to this recall. I did not repair, as I was told the entire thing will need to be replaced.
Other or unspecified, Visibility/wiper, Mar 11, 2025
Panoramic roof explode sound like a gunshot but the roof exploded
Other or unspecified, Lane departure, Feb 7, 2025
Check engine light came on, it has to be with the Positive Crankcase Ventilation Valve. So I found out that other people are experiencing the same thing. So I know that there is a recall by the manufacturer. And I want to do the same for me.
Other or unspecified, Feb 4, 2025
Crank case ventilation Valve needs replaced. This is a hazard and multiple Mercedes owners have reported the same issues.
Other or unspecified, Sep 3, 2024
The rear subframe rusted and needed complete replacement. The service department would not pass the car for inspection without replacement. My brother, who also has a Mercedes C300 model but from the prior year, reported that he had the exact same issue. However, Mercedes issued an extended warranty on his model. In researching this issue, I have discovered that this rusted subframe issue is prevalent in C300 models in all years, not just the model years before mine. I compared the service notes from my invoice with my brother's invoice. It is the exact same issue. I contacted both the Mercedes dealership and Mercedes corporate about this issue, seeking resolution. I provided them with all the documentation. Their answer is simply that my VIN does not qualify under their extended warranty and refused to look into it further, despite my pointing out that it is the exact same problem.
Structure, Other or unspecified, Jun 23, 2024
My boyfriend and I were driving my 2015 MB C400 down the road in November 2020 and it was a beautiful day out so we decided we would open the sunroof to get some fresh air. I was driving so my boyfriend pressed the button for the sunroof to open. As the sunroof was opening, there was a cracking and popping sound coming from above us. We immediately pulled over at a gas station to see what was happening. Upon getting out of the car and looking closer at the sunroof, we noticed many cheap plastic components that were just broken and crumbled laying inside the sunroof tract. We removed the broken pieces and then tried to close the sunroof several times. T Each time, the sunroof went into the closed position BUT immediately went straight back to the popped up position and would not completely close again. I took my car to the MB dealership in Athens, Ga where they told me it would be almost $2500 to repair which I did not feel as if I should be held responsible for as I had just purchased the car in January 2020 only 11 months earlier. I was in fear that the sunroof would detach from the car and cause serious injury to any motorist behind me. I also have a [XXX] son who is now scared to ride in my car!! After doing much research on this issue, I have found that this is truly a common problem with this MB model. I have reached out to the corporate office a few times and they only tell me that there is no active recalls with my cars VIN. It is completely unacceptable that MB is fully aware of this issue yet they continue to disregard the potential harm to other motorists. Please help!!! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Other or unspecified, Jun 19, 2024
Crankcase ventilation valve. PCV valve has failed causing check engine light. Very common issue on this model according to my research. The dealer does not have this product in stock to facilitate a repair and no support to find the part. Very difficult when trying to pass an emissions test and this is the last thing holding that back.
Steering, Air bags, Other or unspecified, Apr 17, 2024
My car is a 2015 Mercedes Benz, I bought it at the agency in 2022. When I tested the vehicle at the agency, I noticed the steering was a little hard. I asked the sales person and he told me it was normal. Then, after 1 year and 5 months, it was on its way. I went to work and the steering wheel jammed and it wouldn't cross and the car turned off then it didn't want to start and it said the following on the dashboard power stering see operator manual
Other or unspecified, Apr 11, 2024
I got an oil change since it was due then “P052E” It’s a very common issues with the engine first time it’s happened at 66K miles.