Vehicle has ongoing and recurring electrical and engine-related defects that affect safe operation. The primary systems involved are the electrical system, engine ignition system, and powertrain. The vehicle is available for inspection upon request. Prior service records show issues beginning in 2020 involving repeated electronic system failures requiring multiple repairs and component replacements. Since purchasing the vehicle in April 2023, the vehicle has developed more serious failures, including: – September 2024: Check engine light with loss of power and inability to exceed safe driving speeds – October 2024: Engine misfiring due to ignition coil failure requiring replacement of ignition components – September 2025: Additional ignition coil electrical fault (code P0353) The problem has been reproduced and confirmed through dealership service inspections and diagnostic reports. Warning indicators, including the check engine light, appeared prior to failure events. These defects create a safety risk due to potential loss of power, engine failure, and unreliable vehicle operation while driving, which could increase the risk of an accident. The issues have required multiple repairs without permanent resolution and appear to be ongoing and worsening over time.

Source: NHTSA complaint ODI #11733212 · view all complaints for this vehicle at nhtsa.gov

The contact owns a 2020 Mercedes-Benz C300. The contact was reversing out of her driveway at 3 MPH, the contact was using her rearview camera. The contact stated that the image froze and she crashed into a parked vehicle with the rear passenger side bumper of her vehicle. The contacts bumper was scratched and dented. The other vehicle had sustained a large dent in the driver’s side door. The contact stated no warning light was illuminated. The contact had taken the vehicle to a local repair and not a dealer or an independent mechanic. The vehicle had been repaired cosmetically. The manufacturer had not been informed of the failure. The contact had received the manufacturer recall letter and related the accident to NHTSA Campaign Number: 22V232000 (Back Over Prevention). The failure mileage was approximately 6500.

Source: NHTSA complaint ODI #11475739 · view all complaints for this vehicle at nhtsa.gov

points: ⸻ While driving, the vehicle displays the warning “Active Brake Assist Functions Limited – See Operator’s Manual.” The message appears during normal driving and does not go away. This warning indicates that the automatic emergency braking / Active Brake Assist system is limited or disabled, reducing a critical safety feature designed to help prevent or mitigate collisions. This creates a safety risk because the vehicle may not automatically brake in an emergency situation. The warning appeared suddenly while driving, with no visible obstructions, weather conditions, or damage to sensors. Restarting the vehicle does not consistently clear the message. The issue has not yet been inspected by a dealer or repair facility. The cause of the malfunction is UNKNOWN, and the vehicle is available for inspection.

Source: NHTSA complaint ODI #11710171 · view all complaints for this vehicle at nhtsa.gov

Uneven wear pattern.The wear often occurs on inner shoulder of the tires 5k to9k miles,which can be dangerous tire can wear down to belts on inside edge while the outer tread still looks fine. i have brought this to dealership multiple time with NO FIX but to sale me new tires and alignments.I have spoke to multiple owners of 2020 mercedes c63 and they have the same problem. This is a safety issue and has left my wife and kids on the side of freeway broken down.

Source: NHTSA complaint ODI #11697729 · view all complaints for this vehicle at nhtsa.gov

I purchased this vehicle on December 26, 2025 from an authorized Mercedes-Benz dealership. Shortly after the purchase, I discovered an issue related to the airbag system, which indicates a potential safety defect. At the time of purchase and during the test drive, the vehicle was already turned on, and no warning or disclosure was provided regarding any airbag malfunction or warning message. The issue became apparent only after the purchase. I later brought the vehicle in for repairs. While some repairs were performed, the airbag issue was not fixed and remains in the same condition as before. The dealership is now refusing to repair the airbag system at no cost and is insisting that I pay for the repair, despite the fact that this defect appeared immediately after purchase and was never disclosed to me. I believe this represents a serious safety concern, as a malfunctioning airbag system may fail to protect occupants in the event of an accident. I also believe the vehicle was sold to me with an undisclosed safety defect. I am requesting that this issue be formally reviewed and investigated.

Source: NHTSA complaint ODI #11712823 · view all complaints for this vehicle at nhtsa.gov

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.

Source: NHTSA complaint ODI #11754327 · view all complaints for this vehicle at nhtsa.gov

THE COMPONENT THAT IS MALFUCTIONING IS THE COVERTABLE TOP OF MY 2020 C300 CABRIOLET MERCESDES BENZ. THE STRINGS/CORDS THAT HOLD THE LINER OF THE COVERTABLE TOP TO THE ROOF ARE BREAKING AND IT MAKES THE COVERTIBLE TOP INOPERABLE. THERE WAS NO WARNING LAMP OR NOTICE OF THIS DEFECT. THERE IS ONLY 11595 MILES ON MY 4 YEAR OLD CAR THAT IS GARAGED. THIS OCCURRED 1 YEAR AFTER MY WARRANTY EXPIRED. THIS WOULD CAUSE THE TOP TO BE STUCK IN THE MIDDLING OF OPENING AND IT COULD NOT BE MOVED MECHANICALLY TO GET IT FULLY OPENED OR CLOSED TO THE WEATHER AND IS UNDRIVABLE.THE COST TO REPAIR IT IS ESTIMATED BY THE DEALER AT $4,000.00. tHE DEALER IS WELL AWARE OF TGIS LATENT DEFECT.

Source: NHTSA complaint ODI #11635599 · view all complaints for this vehicle at nhtsa.gov