75 of the
669 complaints filed about the Mercedes Benz C 300
are about the other systems —
11% of everything owners reported.
The worst model year for it is 2017.
Transmission failed, yes available for inspection Very bad safety issue Yes it has been confirmed by dealship Yes by the deanship Yes there was warning lamps that appeared in January 2026
NHTSA complaint #11744612 — 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 car jerks so hard at times randomly that it feels like I got rear ended and it is completely unsafe. It also does small jerks at times. It's happened driving 70 mph down a highway, making a right turn accelerating slowly. Going slow down the street at 35, at a red light completely stopped or stop sign. There's no rhyme or reason to it. I've taken it to Mercedes five or six times now with the same issue and they have not been able to duplicate the problem. It's currently at Jacksonville Mercedes dealership where I bought it with the foreman. He is with my permission driving it back and forth to work because I said I do not want the car back until they can duplicate the problem and fix it or recall it or give me a new one or give me my money back. One of the instances that jerked so hard that it hurt my back. None of the sensors go off when it's plugged in while they're trying to locate a problem it only happens when it's being driven and again there's no rhyme or reason to when it happens. It does happen pretty regularly at least 10-12 times hard over the last year and the little ones happen more frequently at least 20 to 30 over the last year the last time being when I drove it on 1/5/26. Miles have been from 200 to 9100. It been happening for a year now. Mercedes Clearwater and Mercedes Jacksonville will have all of the files from the five or six times I've brought it in. I also attempted to get a lemon law request through Mercedes executive services in March or April which they denied because they couldn't duplicate the problem, but there was never a serious attempt to duplicate it by Mercedes until now that it's at the Jacksonville location where I purchased it from. The Foreman and GM there are taking it more seriously and the foreman again is driving it back and forth to work in hopes of duplicating the problem.
NHTSA complaint #11709707 — an unverified report by a vehicle owner.
I think the recall is on communication software. I contacted Mercedes Benz many times in the past 2 years. Mercedes Benz asked its dealer to do the recall but dealer said they cannot do it. Mecedes Benz also said their software supplier had not found a solution yet.
NHTSA complaint #11698435 — an unverified report by a vehicle owner.
Rearview Camera is not displayed when the vehicle is placed in reverse. The display shows a black screen. A Recall Notice has been published for other vehicles of the same year, make, and model. The failure of the Rearview Camera results in safety risks during normal use of the vehicle.
NHTSA complaint #11692113 — an unverified report by a vehicle owner.
I am writing to formally report an ongoing issue and safety concern with my vehicle. Since the day I purchased the car, I have experienced numerous mechanical problems and have spent a significant amount of money on repairs. In August, I had to take my vehicle to a local repair shop three times due to persistent issues. The car was also towed by AAA three separate times for safety reasons. My main concern is that the vehicle hesitates during acceleration and feels sluggish while driving, which creates a serious safety risk on the road. I contacted Mercedes-Benz and filed a claim regarding this issue; however, I have not received any meaningful assistance or resolution. I am requesting that this matter be re-evaluated and properly addressed as soon as possible, as my safety and the reliability of the vehicle are at risk. Please confirm receipt of this message and advise me on the next steps or any documentation needed to proceed with my claim. Thank you for your prompt attention to this matter. [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11691362 — 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.
My panoramic sunroof spontaneously exploded while driving down the highway, no external impact was made. The glass exploded from the inside out. It made a loud boom, it startled me on the highway resulted me to swerving on the road, which would have put me and other drivers at risk. There's plenty other MB drivers reported similar issues that stated. MB has also settled a class action lawsuit regarding such manner. UNKNOWN There were no warning signs prior to the event. The event spontaneous and sudden.
NHTSA complaint #11678947 — an unverified report by a vehicle owner.
In October 2024, the rear subframe was replaced due to rust perforation in the area of the suspension arm mounting bracket. I had no warning. The car was in for routine service at Mercedes Benz of New London. It had rusted from the inside out and was considered unsafe to drive by the Mercedes service advisor. I could have had a serious accident! I had no choice but to replace the subframe as it is my only vehicle. Shockingly I learned many others have had this issue with various Mercedes models/years and that Mercedes Benz knows of this serious safety problem and there is a class action lawsuit pending but subframe replacement is not covered under warranty by Mercedes Benz, so the cost was mine to bear.
NHTSA complaint #11676702 — an unverified report by a vehicle owner.
The sunroof is very glitchy and this is common in all Benz I have had a few different Benz and they all eventually have this same issue with their panoramic sunroof. Sometimes it opens half way life one side is up and the other side is closed and other times it will open fully but not close and other times it won’t open at all. This is a common problem that many Benz owners have stated this in the Benz forums all over. This is a safety issue due to unexpected weather conditions if it rains and it’s stuck inside gets damage and owners get wet which is also a distraction and may cause accidents. Please investigate this issue thoroughly. Their sunroofs should be recalled and extended warranties placed on them automatically by Mercedes Benz due to this being a very common issue in all model’s panorama sunroofs particularly C300s year 2017 thank you for looking into this matter.
NHTSA complaint #11665836 — 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.
Error code P052E71 on a 2017 c300 with 100k miles. It seems to be a very common and recurring issue that appears to have no real solution and is costing consumers thousands upon thousands. This malfunction does relate to emissions and this vehicle is operated in California.
NHTSA complaint #11635619 — an unverified report by a vehicle owner.
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.
NHTSA complaint #11635599 — an unverified report by a vehicle owner.
The valve for crankcase ventilation has a malfunction. The actuator is blocked Select 'Error codes / Events' menu in Engine Control Unit. Then read fault memory.
NHTSA complaint #11625696 — an unverified report by a vehicle owner.
The manufacturer recalled car due communication module's SIM card software problem more than 2 years ago. I went to the dealer where I bought the car and also contacted the manufacturer several times but still have not been able to solve the problem.
NHTSA complaint #11625732 — an unverified report by a vehicle owner.
I was leaving a gas station after pumping gas, and as I began to turn onto the road my car failed to respond in any way. It would not accelerate or break, the wipers suddenly came on and the headlights and emergency lights began blinking off and on. I was 1/2 second from being t-boned in the driver-side door by an oncoming Ford F350. The Ford F350 driver lost control of their vehicle trying to swerve to avoid hitting my car and did a 360-degree turn in the middle of the road, almost being hit multiple times by other vehicles because the Ford F350 ended up in the lane of oncoming traffic. Only by the Grace of God no one was seriously injured or killed. The SC State Trooper coincidently witnessed the incident and said I should contact the NHTSA, to report what happened when I understood what would cause the car to become incapacitated mid-operation. My car would not turn off and NONE of the controls to anything in the car would work. It took the tow truck driver over 2 hours to figure out what fuse to pull to force the car to turn off before it could be towed. It was towed to the Mercedes dealership on Laurens Road, Greenville SC. 9 weeks later, last week, I got a call from the service tech, he explained to me the drain tubes in my sunroof were clogged, which caused water to flood the front seat floor subcompartments. He said so much water had flooded the subfloor that even 9 weeks later over 3 gallons of water were vacuumed out. The water had caused major damage to the electrical junction boxes in the subfloor and caused them to short out, incapacitating my car while driving. The tech explained there was no way I could have prevented the damage or even known the tubes were clogged, or the subfloor was becoming flooded. There are no maintenance requirements listed for the drain tubes that could have made me aware that the car could become incapacitated while in drive causing serious risk to myself and other drivers. This should be looked into ASAP.
NHTSA complaint #11624574 — an unverified report by a vehicle owner.
I purchased my 2017 Mercedes c class coupe in 2020, used. Around 2021, I started hear noise from the sunroof when driving on the highway. I went to get it repaired and they mentioned they needed to tighten the screws. This week, I was closing my sunroof and then I heard a crack. I went to a shop to get it manually closed for now on calis 105 degree heat. I am now learning there has been recalls for Mercedes 2017+ coupes but it’s not stated for my specific car to get it fixed. How do I go about this? I feel the sunroof is faulty and has been faulty.
NHTSA complaint #11613280 — an unverified report by a vehicle owner.
The same part that was recalled the Starter Current Limiter has overheated again. The dealership is trying to charge for this same part for diagnostic, parts and labor. The car produces smoke around the battery and melted due to overheating. The battery is new. The car only turns over..then immediately overheats. Just because it was recalled and replaced does NOT mean it is perfect from defaulting again. Please have someone look into this matter.
NHTSA complaint #11610018 — an unverified report by a vehicle owner.