50 of the
669 complaints filed about the Mercedes Benz C 300
are about the body and structure —
7% of everything owners reported.
The worst model year for it is 2017.
I own a 2020 Mercedes-Benz C300 equipped with a power trunk. On July 22, 2026, I took my vehicle to Annapolis Mercedes-Benz because the power trunk was repeatedly closing on its own while people were standing in the trunk opening. I specifically reported that the trunk was unexpectedly closing while I, my child, or another individual was loading or unloading the vehicle and expressed concern that someone could be injured. The dealership kept the vehicle for several hours but advised me that no malfunction could be found. I was told the trunk had been reset and that there were no problems with the vehicle. I also provided video evidence of the trunk malfunction by text message to my service advisor. On August 2, 2026, the exact same problem occurred. While I was loading groceries into the trunk, the power trunk unexpectedly closed without warning and struck my son in the head, causing injury. This incident occurred after I had already reported the same safety concern to the dealership. I believe the power trunk is malfunctioning intermittently and presents a significant safety hazard because it can unexpectedly close on a person while the trunk is being used. I am requesting that NHTSA investigate this potential safety defect, as it may pose a risk of injury to other vehicle owners and passengers.
NHTSA complaint #11754327 — an unverified report by a vehicle owner.
Automatic trunk closing mechanism caused the trunk hood to close on my head as I was putting groceries in the trunk. This has occurred several times in the past but this time it hit my head with more force. I have not brought it to a dealer and it has not been inspected by the manufacturer, police or any other entity. There was no warning or alarm before it closed. This could cause serious head injury to an individual on blood thinners.
NHTSA complaint #11747837 — an unverified report by a vehicle owner.
The panoramic sunroof unexpectedly shattered while the vehicle was parked in my driveway overnight. There was no collision, impact, weather event, vandalism, or any other external cause that could explain the failure. The damaged sunroof remains available for inspection upon request, and security camera footage from my property shows no outside influence that could have caused the glass to break. The unexpected failure of the panoramic sunroof created a significant safety risk. Had this occurred while I was driving, shattered glass could have fallen into the vehicle, potentially causing injury to me or my passengers, obstructing visibility, or leading to a loss of control of the vehicle. The fact that the glass failed without warning while the vehicle was stationary raises concerns about the safety and structural integrity of the panoramic sunroof system. The dealership claims that they inspected the vehicle and confirmed that the panoramic sunroof was shattered. However, they did not want to provide me with the inspection report and denied the claim responsibility and have not acknowledged the failure as a manufacturing defect. The vehicle has been inspected by the dealership. No police report was filed because there was no accident, vandalism, or criminal activity involved. At this time, the manufacturer has not independently inspected the vehicle to my knowledge. As I have seen and read online, there has been dozens of similar cases with Mercedes regarding this issue and I believe i have read there is a lawsuit. No warning messages, no recalls, no unusual noises, cracks, chips, leaks, or other symptoms were present prior to the failure.
NHTSA complaint #11741578 — an unverified report by a vehicle owner.
The contact owns a 2019 Mercedes-Benz C300. The contact stated that while driving and attempting to close the sunroof, the sunroof made an abnormal popping sound. The contact pulled over and attempted to close the sunroof, but the sunroof failed to close. The contact related the failure to NHTSA Campaign Number: 21V197000 (Structure); however, the VIN was not associated with the recall. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The manufacturer was not contacted. The failure mileage was approximately 53,000.
NHTSA complaint #11729410 — an unverified report by a vehicle owner.
The contact's wife owns a 2018 Mercedes-Benz C300. The contact stated that while washing the vehicle, a part of the panoramic roof started moving while depressing the glass. The contact stated that there was water leaking into the vehicle from the glass. Upon investigation, the contact discovered NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included in the recall. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was filed. The manufacturer confirmed that the VIN was not included in the recall. The contact was then referred to the NHTSA Hotline to report the failure. The failure mileage was unknown.
NHTSA complaint #11722229 — an unverified report by a vehicle owner.
The contact owns a 2019 Mercedes-Benz C300. The contact stated that the convertible top support were fraying. The contact stated the parts were almost the thickness of a shoelace and enabled the convertible top to fold correctly when the top was folding down. The contact stated that the Part Number was A2057780500. The contact had taken the vehicle to a local dealer, where it was diagnosed, and the dealer determined that the entire convertible top needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure, and the contact filed a case. The failure mileage was approximately 43,000.
NHTSA complaint #11704696 — an unverified report by a vehicle owner.
The contact owns a 2017 Mercedes-Benz C300. The contact stated that while driving 65 MPH on the highway, the contact heard a popping sound coming from an unknown part of the vehicle. The contact pulled over to the side of the road, exited the vehicle, and became aware that the roof panel had shuddered. The contact stated there was no glass in the vehicle. No injuries were sustained. The contact stated that the failure had occurred on two occasions. The vehicle was not taken to an independent mechanic or the dealer to be diagnosed. The vehicle was taken to the dealer by the previous owner to be repaired under NHTSA Campaign Number: 21V197000 (STRUCTURE); however, the recall repair failed to prevent the failure. The manufacturer was notified of the failure and informed the contact that there was no recall related to the failure. The manufacturer offered the contact a trade for the vehicle. The failure mileage was 105,000.
NHTSA complaint #11697621 — an unverified report by a vehicle owner.
I am reporting a serious vehicle safety hazard caused by improper and unsafe repair work performed by USA Platinum Motor, located at 1221 California Lane #126B, Arlington, TX. I brought my 2017 Mercedes-Benz C300 in for a cold start rattle with no warning lights or prior issues. The shop diagnosed a loose timing chain and I authorized the repair. After the repairs, the vehicle was returned with critical safety defects, including a loose fuel pump, unsecured fuel line, missing bolts, and improperly reassembled engine components. Shortly after pickup, the car experienced loss of acceleration on the interstate, a strong odor of fuel, and a sudden loss of power, creating a dangerous and life-threatening situation. The vehicle had to be towed back to the shop. The manager, who is not a certified mechanic, admitted he personally “fixed” the issue by tightening the fuel pump himself. A Mercedes-Benz diagnostic inspection later confirmed multiple severe assembly errors, including missing fasteners, unsecured oil cooler, disconnected vent lines, and other safety-related defects in the fuel and cooling systems. These unsafe and negligent repairs created an extreme fire hazard, engine instability, and risk of sudden failure while driving. I am requesting a formal NHTSA investigation into this matter to ensure vehicle safety compliance and to prevent similar incidents affecting other consumers.
NHTSA complaint #11696497 — an unverified report by a vehicle owner.
This is the same as recall for NHTSA ID: 21V-197. The panel flew off my 2017 Mercedes C300 W205. My vin number is not included in the recall. This is a safety issue and will need to be replaced.
NHTSA complaint #11695341 — an unverified report by a vehicle owner.
I was driving on the hwy 94 in Minneapolis and I had the cap to my sunroof fly off on the freeway. There’s a recall out on the sale vehicle but 4matic but not on my vin number. This is a huge safety issue and it’s been happening to quite a few people I know. No one was injured and it didn’t cause damage to any other vehicle but when I brought it into the shop they said the recall that was on this part was not for my exact vehicle.
NHTSA complaint #11691716 — an unverified report by a vehicle owner.
The contact owns a 2018 Mercedes-Benz C300. The contact stated that while driving approximately 60 MPH, a part of the panoramic roof towards the driver's side detached from the vehicle. The contact pulled over to inspect the vehicle. The part was no longer attached, and the contact had to continue driving. The failure caused additional electrical failures due to water entering the cabin of the vehicle. The contact stated that the sunroof failed to open, and the infotainment center was inoperable. The contact found information on NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included. The vehicle was taken to the dealer, who related the failure to the recall; however, the vehicle could not be repaired under the recall because the VIN was not available. The vehicle was not repaired. The manufacturer was informed of the failure and opened a case. The manufacturer confirmed that the VIN was not included in the recall. The manufacturer referred the contact to the NHTSA Hotline to file a complaint. The failure mileage was approximately 109,000.
NHTSA complaint #11681537 — an unverified report by a vehicle owner.
The contact owns a 2017 Mercedes-Benz C300. The contact stated that while driving at 60 MPH, the contact became aware that an unknown part had detached from the vehicle. The contact stated that after stopping to refuel the vehicle, it was discovered that the roof panel was missing. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The contact related the failure to NHTSA Campaign Number: 23V854000 (Structure); however, the VIN was not included in the recall. The manufacturer was not made aware of the failure. The failure mileage was approximately 129,000.
NHTSA complaint #11681330 — an unverified report by a vehicle owner.
The sunroof exploded spontaneously while driving to a destination. When the incident happened, I was stopped at a red light. I panicked as it sounded like gunshots hitting my car. I pulled over to the nearest safest destination to inspect the car. This put the safety of myself at risk and others at risk who were driving along the sides and/or behind me. This incident was confirmed by a dealer, as I went to Mercedes Benz Sugar Land on the following day of the incident and was quoted around $3,700 to have it repaired. The vehicle not been inspected by police and/or insurance. There were no warning signs that this could have happened besides the fact that Mercedes Benz USA is currently under an active lawsuit for this happening to several other drivers. I do believe that this is a manufacturing defect affecting safety, as similar incidents involving Mercedes-Benz panoramic sunroofs, which may indicate a wider defect trend.
NHTSA complaint #11680437 — an unverified report by a vehicle owner.
The contact owns a 2020 Mercedes-Benz C300. The contact stated that a section of the roof near the top of the windshield, between the sunroof, had detached and flown off the vehicle while driving 30 MPH in bumper-to-bumper traffic. The driver was able to grab the portion of the rubber gasket and pulled it into the vehicle through the driver’s side front window. The roof was in three pieces. The contact turned on the hazard lights and was able to pull over safely to the side of the roadway. There were no warning lights illuminated. The contact was concerned about the failure potentially causing a road hazard under different circumstances. The vehicle was taken to an independent mechanic the next day who declined to service the vehicle and informed the contact it was an issue for the manufacturer. The contact went to a body shop and was informed that the failure was caused by a design flaw. The contact called the local dealer, who initially did not respond. The contact called the dealer again, who requested photos. The vehicle was taken to the local dealer, who declined the repair the vehicle and escalated the issue. The vehicle was not diagnosed or repaired. The manufacturer was contacted regarding the failure and opened a case, but no decision had been made regarding the repair coverage. The failure mileage was approximately 28,722.
NHTSA complaint #11678311 — an unverified report by a vehicle owner.
The contact owns a 2018 Mercedes-Benz C300. The contact stated that after washing the vehicle, the contact became aware that the adhesive attaching the rear window to the convertible top had started to detach. Upon further inspection, the contact became aware that water had seeped into the vehicle through the crack. There was no warning light illuminated. The local dealer was contacted; however, the vehicle was not diagnosed. The contact was also informed that the VIN was not under recall. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 49,000.
NHTSA complaint #11664906 — an unverified report by a vehicle owner.
While driving at 60mph my panoramic sunroof completely shattered. Nothing at all hit the sunroof to cause it to shatter. If my sunshade cover had not been on, the glass would have fallen on me while operating my vehicle. This is not only dangerous but unacceptable. It was also a distraction that could have caused an accident. Mercedes did not make me aware of the class action lawsuit they have with the panoramic sunroofs, and I feel that was neglectful on their part. Upon inspection from a service advisor at a Mercedes Benz dealership, they told me something must have hit it (nothing hit it) and want to charge me $4,000 to fix it.
NHTSA complaint #11662742 — an unverified report by a vehicle owner.
When i scan my vehicle there are Mercedes Benz fault codes pertaining to the electrical system but also recalls that haven’t been done but when looking Mercedes Benz web site and NHTSA WEBSITE these are aren’t showing up as my particular chassis being included as part of the campaign
NHTSA complaint #11621666 — an unverified report by a vehicle owner.