2016 Mercedes-Benz C 300 Body & structure Problems

Premature corrosion of rear subframe. See attached letter for further details.

NHTSA ID

11776450

Incident

Oct 21, 2026

Rear sub frame has rusted through and according to repair shop cannot be safely driven until repaired. Mercedes has granted extended warranty for sub frame rust through for the C300 up to model year 2015 so this is a known problem. My car is a 2016 and Mercedes will not offer the extended warranty.

NHTSA ID

11771705

Incident

Oct 9, 2026

The contact owns a 2016 Mercedes-Benz C 300. The contact stated that while performing maintenance on the vehicle with the dealer, it was discovered that the rear subframe was severely rusted and perforated. The contact associated the failure with Technical Service Bulletin: MC-10232321-0001; extended warranty, but vehicle was not included. The manufacturer was contacted by phone and made aware of the failure. The failure mileage was approximately 84,616.

NHTSA ID

11769311

Incident

Sep 2, 2026

Mileage

84,616 mi

Panoramic sunroof fails to open/ close evenly due to binding issue and plastic track failure. One side binds while the other moves, causing glass to tilt and jam. Risk of dangerous injury including glass shattering, sudden detachment, distraction while driving, and water intrusion affecting airbags/electronics.

NHTSA ID

11733700

Incident

Feb 27, 2026

The contact owns a 2016 Mercedes-Benz C300. The contact stated that while driving approximately 20 MPH and turning the steering wheel to the right or the left, there was an abnormal clicking sound coming from the rear of the vehicle. There was no warning light illuminated. The contact had taken the vehicle to a local dealer where it was diagnosed and determined that the rear sub frame of the vehicle had severe corrosion and needed to be replaced. The contact was advised by a service technician that there had been a recall for corrosion failures, but the year and the model were not included. The vehicle was not repaired. The manufacturer was informed of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 130,000.

NHTSA ID

11716937

Incident

Sep 10, 2025

Mileage

130,000 mi

* Component Failed / Malfunction - Panoramic Sunroof Separation. The front roof panel located between the windshield and the panoramic sunroof has separated from the windshield panel. * Sun roof glass panel is at risk of separating for car and becoming airborne causing injury to driver and others. * Problem has been confirmed by independent service center. * First appeared on approximately April 21, 2025.

NHTSA ID

11662284

Incident

Apr 21, 2025

Rusted rear subframe, dime size hole discovered by Mercedes technician on [XXX]. The Mercedes dealer who discovered it was Mercedes Benz of Fredericksburg, VA. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11650695

Incident

Dec 4, 2024

--The sunroof glass suddenly shattered without any prior warning while the vehicle was in driving on the road. Some of the broken glass pieces scattered throughout the interior of the car. --The sudden shattering of the glass roof created a hazardous situation for the driver and passengers. Although no one was injured, we were shocked and initially thought it might be an explosion or gunfire. Additionally, the tiny glass shards is very dangerous. --We have called dealer and they said there might be several similar cases reported. --The vehicle has not yet been inspected by the manufacturer, police, or insurance representatives, but I have called dealer and insurance company. --There were no warning lights, messages, or symptoms indicating a potential failure before the incident. The glass shattered unexpectedly and spontaneously while driving.

NHTSA ID

11643527

Incident

Feb 17, 2025

the roof panel cracked straight down the middle

NHTSA ID

11632895

Incident

Dec 26, 2024

On [XXX] I was on my way home from running errands and proceeded to open my panoramic sunroof using the button inside of my car. When I arrived home, I pressed the button again to close the sunroof. As it began closing and went into the forward position, once it reached the top of my roof, the back of the sunroof would not go down back into place. This left the sunroof open in the venting position. On [XXX], I went to RBM of Atlanta where I purchased the vehicle [XXX] to report and resolve the issue. The service center was rude and brushed off my concerns. They were able to manually close the sunroof as a temporary fix and informed me not to use the sunroof button, but they were unable to assist with my diagnostic or repair inquires. However, one of the service employees advised that this was a common issue that was previously recalled. I immediately contacted MBUSA where I was connected to a Sales rep at RBM of Atlanta who also informed me that this was a common issue. Today, 07/24/2024, I went to a diagnostic appt. at RBM of Alpharetta and was told by the service advisor that there had been at least 9 recalls for this issue and my sunroof has all of the defective parts that were supposed to be replaced when these recalls took place. He also informed me that I should have been advised of this issue before the vehicle was sold to me. I have attempted to resolve the issue with RBM on five different occasions to no avail. My vehicle is available for inspection upon request. I believe this issue puts myself and others at risk because if the entire sunroof is defective, it can detach at anytime and possibly hit and injure someone while I'm driving, which would make me liable. As stated previously, I have received confirmation that my sunroof is defective and should have been added to one of the several recalls. The last multi-point inspection was done nearly a year before I bought the car and a repair diagnosis was done today. There were no other signs. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT

NHTSA ID

11604321

Incident

Jul 15, 2024

The complaint is about the sunroof which has an open recall with all warning signs and risks exactly identical to my make, year and model (2016 mercedes benz c300). More than 15,000 vehicles have been affected by this problem and the warning signs suddenly appear with the vehicle. Mercedes Benz after their investigation after several reports were filed, later found that the sunroof glass panels were installed without prior application of the primer (bonding agent) which was supposed to ensure the specified strength of the bonded joint. NHTSA received several complaints concerning this issue where the sunroof suddenly began shaking and rattling which began with the driver noticing excessive wind noises in the area of the sunroof while driving indicating that the panel might be partially separated from the vehicle. I began noticing this on Tuesday May 28th, 2024, when my sunroof tilted open on the left side and failed to open properly. Upon closing it, I began to drive, and the wind noise and excessive rattling was immediately noticeable. It sounded like the wind was forcing open my sunroof and was almost like the wind was about to pull it out. In fear, I slowed down to about 20mph, but it was still very noticeable. I got scared and immediately pulled to the side of the freeway and parked. Then I immediately looked up the issue on google and noticed that there was an open recall for the exact same issue, for my make, model and year. It was noted that the roofs if not fixed will eventually pull out and flyaway posing a safety risk to the driver and other motorists who may crash as they try to avoid the debris or if the panel hits them. Luckily, I pulled over quicky out of fear for it felt like my sunroof was literally about to pull off by the wind. Now I am unable to drive my vehicle because of fear for my safety. Please I would appreciate if this were resolved and for my vehicle to be recalled and fixed immediately as soon as possible. Thanks.

NHTSA ID

11591312

Incident

May 28, 2024

Panel between windshield and sunroof is peeling off loosing the clear coat even when the car is only 40.000 miles and is inside the garage

NHTSA ID

11584263

Incident

Apr 2, 2024

Front Stationary Sunroof Panel (between the windshield and the sunroof) deteriorating and cracking in the middle. I've read about a recall on previous year models that will extend to this year model or even further year but waiting on this recall to reach my vin number. I've seen same model year in other states have this issue resolved with the recall update in Feb 2024. This is related to the NHTSA Recall ID: 23V854.

NHTSA ID

11581170

Incident

Sep 1, 2022

I took my car for service "B" at the dealership. They told me the rear subframe is rusting and there is a hole forming already. Apparently, this is a known problem that Mercedes Benz provided warranty extension up to 20 years with unlimited mileage. However, they stopped at 2015 models. Mine was bought from the same dealership in October 2015, but it is a 2016 model, but actually has the exact same problem earlier models have and they cover with their voluntary extended warranty. I am told to replace it, it will cost at least $4600. They are refusing to cover it under warranty because I my car is at around 60,000. The car did not even reach 100K and well maintained, but has rusted frame already that can be a serious safety hazard according to Mercedes Benz associate.

NHTSA ID

11572113

Incident

Feb 9, 2024

The panoramic sunroof gets stuck on passenger side, and came off the rail on the passenger side as i was driving on the freeway

NHTSA ID

11566312

Incident

Jan 18, 2024

Panoramic sunroof is closing right way. While when i drove air comes in .

NHTSA ID

11531569

Incident

Jul 4, 2023

the Burl wood trim panel on the interior doors are deteriorating , the drivers side panel is deteriorating to the point that it looks like acid is eating away at the material there is red markings showing .. i find this could be a safety hazard as it could eat away at the door itself. i have pictures of evidence. there was a recall on Mercedes E class during the same years i purchased my car, my car is the C-class which was not part of the recall, but falls into the same category as time frame of purchase. Mercedes told me to contact you. i look forward to your response as this is a safety concern thank you

NHTSA ID

11493595

Incident

Sep 1, 2022

exterior fixed front roof panel cracking and causes potential roadway dangerous situation if pulls off roof while driving

NHTSA ID

11461494

Incident

Apr 20, 2022

Gas smell while driving.Not reported

NHTSA ID

11456951

Incident

Mar 1, 2021

Panoramic Sunroof deterioration, which caused the sunroof to get stuck due to fragments in the sliding area. Sunroof unstable. Unable to ride with it open and makes a whistling sound when closed.

NHTSA ID

11434104

Incident

Sep 18, 2021

The contact owns a 2016 Mercedes-Benz C300. The contact stated while driving approximately 50 mph, an abnormal sound was heard as a section of the glass roof panel detached from the roof of the vehicle. The vehicle was taken to an independent mechanic who replaced the missing panel. The cause of the failure was not determined. The contact later received notification of NHTSA campaign number 21V197000 (Structure) however, the part to do the recall repair was not available. The local dealer was contacted, and it was confirmed that the part was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was 31,000. Vin tool confirms parts not available.

NHTSA ID

11424103

Incident

Oct 13, 2020

Mileage

31,000 mi

The contact owns a 2016 Mercedes-Benz C300. The contact received a recall notification for NHTSA Campaign Number: 21V197000 (Structure) however, the part to do the recall repair was not yet available. The dealer was contacted and confirmed that parts were not yet available to for the recall repair. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not notified of the issue. The contact had not experienced a failure. Vin tool confirms parts not available.

NHTSA ID

11423782

Incident

Jul 7, 2021

PLASTIC PANEL BETWEEN WINDSHIELD AND PANORAMIC SUNROOF DETACHES. ADHESIVE DEGRADES OVER TIME CAUSING PANEL TO NOT BOND WITH THE BODY.

NHTSA ID

11415776

Incident

May 9, 2021

Mileage

53,000 mi

PANORAMIC SUNROOF IS LOOSE NOT PROPERLY BONDED.

NHTSA ID

11403909

Incident

Jan 14, 2021

THE PANORAMIC SUNROOF IS NOT PROPERLY BONDED ON MY 2016, C300 MERCEDES, WHILE DRIVING OVER 50 MPH YOU CAN HEAR THE SUNROOF MAKING A RATTLING NOISE.

NHTSA ID

11399927

Incident

Feb 13, 2021