2022 MERCEDES-BENZ C 300 Complaints

Car fails to accelerate past 25 mph when entering roadway. Roadway area is 45mph and vehicle would not accelerate to reach safe levels. This out myself and occupants of my vehicle in danger as traffic is already at the 45+ mph limit. Vehicle has 30,000 miles. Engine light came on after incident.

Refer to Mercedes Complaint letter dated August 21, 2025. Refer to EDR report of the crash Mercedes Benz is claiming no responsibility for the failure of Active Brake Assist (ABA) during a frontal impact collision that resulted in the car total loss. The sensors also didn't work resulting in no alert to the driver and nothing recorded on the car camera system.

1. The vehicle experienced a fuel injector failure, which is part of the engine fuel delivery system. This failure appears connected to an open Fuel System Control Unit Software Update Recall (Campaign 2024080006) that has been open since May 2024 but was not performed on my vehicle, despite the vehicle being serviced at the dealership in January 2025 for other recall-related updates. The failed injector is still available for inspection upon request. 2. The vehicle began exhibiting symptoms of fuel system malfunction while driving, including rough idling, hesitation, and loss of power. A malfunctioning injector can cause the engine to misfire, stall unexpectedly, or run unpredictably, which creates a high-risk situation in traffic. This placed me, my passengers, and other drivers at risk, especially during acceleration or when merging into traffic. 3. Yes. The issue was diagnosed and confirmed by the Mercedes-Benz dealership, which stated that the injector had mechanically failed. The dealership also noted the open recall for the fuel system software update but claimed it was unrelated. I am seeking clarification because the timing and symptoms suggest there may be a connection. 4. The vehicle has been inspected only by the Mercedes-Benz dealership. Mercedes-Benz USA (MBUSA) has been contacted regarding the issue, but my case was closed without resolution and is currently awaiting review for reopening. MBUSA has not yet inspected the vehicle or the failed component directly. 5.Prior to the injector failure, the vehicle displayed engine hesitation, rough idling, and intermittent performance issues. Eventually, a check engine light illuminated. These symptoms began before the manufacturer-installed software update, and the issue appears to have worsened afterward.

Passenger seat belt doesn’t lock properly sometimes comes out and is very hard to put in on entry of vehicle

All on a sudden the entire screen goes blank. It has happened at least 4 times and each time the service center does some patching and it works for a few month. When it happens, all the safety features are off including reverse camera. Also, no way to set the temperature or turn of the AC. In both cases, it can lead to significant damage. The recent incident happened when I was a very busy area and without any safety feature, the car was pretty much un-drivable.

When starting vehicle, center screen of vehicle was completely off and dark. Moreover, with this screen being off, you are not able to control any of the vehicle functions such as AC, Maps, Radio, Rear Camera, etc. On the other hand, on the digital speedometer screen, a warning message states "Blind Spot Assist Inoperative" and when putting the vehicle in gear, a loud beep sounds within the car and then the next warning message appears that states, "PARKTRONIC" inoperative see owners manual"

The electronic system, specifically the battery, failed and it is available for inspection upon request. The persistent battery drain caused the vehicle to become inoperable multiple times, including an incident where I was stranded 200 miles from home with my wife and dog, posing significant safety risks. Yes, the defect has been confirmed by the dealership’s service center multiple times. The vehicle has been inspected by the dealership’s service technicians. Yes, the first malfunction message appeared on [XXX] at 2:22 PM, a week after purchase. Multiple warning messages have appeared since then, including transmission malfunction, running lights malfunction, high beams malfunction, and additional battery malfunction. Defect Description: - Description of the Defect: Persistent battery drain and related electronic system issues. - Date First Appeared: [XXX], a week after purchase. - Subsequent Occurrences: Multiple instances including being stranded 200 miles from home due to a dead battery and transmission error. Repair Attempts: I have taken my vehicle to [Dealership Name] for repairs on multiple occasions. Despite these efforts, the defect persists. Below are the details of each repair attempt: - Repair Attempt 1: [XXX], 2023, Battery replaced. - Repair Attempt 2: [XXX], 2024, Dealer refused to replace battery and simply charged it. Issue persisted the next day. - Repair Attempt 3: [XXX] 2024, Dealer didn't get back to me yet. Roadside Assistance Calls: - [XXX] 2022: First roadside assistance call for a dead battery. - [XXX], 2024: Roadside assistance called again. - [XXX], 2024: Roadside assistance called again. - [XXX], 2024: Roadside assistance called again. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2022 Mercedes-Benz C300. The contact stated that while the vehicle was parked, the contact became aware that the seal had detached from the driver’s side front door. The contact stated that due to the failure, water entered the driver’s seat causing a short circuit in the electrical system. The vehicle was taken to a dealer and was determined to be a manufacturing defect. The vehicle was not repaired. The manufacturer was made aware of the failure and referred the contact to the NHTSA Hotline. The vehicle was not repaired. The failure mileage was approximately 6,000.

I am attempting to submit a complaint against the Mercedes-Benz product and other auto manufacturers that follow this process. Mercedes provides no spare tire so this has been replaced by a "fix a flat" system that you can presumably use stop a tire air leak and then drive to a shop for repair. The fix a flat does not work when the tire is blown out or shredded so when this happens you are left with needing to have the vehicle towed to the dealership if using Mercedes' Roadside Assistance or to another shop at your own expense. Towing to a Mercedes dealership captures you to use the replacement parts in their inventory and costly labor charges. The time it takes to replace a tire is ridiculous considering a spare tire could be put on in a fraction of the time. There are approx. 30k miles on our vehicle and it has had to be towed twice for tires where the fix a flat did not work. Is this a safety issue? Absolutely, if you are driving outside of a city and the tire blows out then you are left with few options to resolve this and you better be in an area with cell phone coverage to contact Roadside Assistance otherwise you are stuck. I understand that "run flat" tires are now used but then why didn't Mercedes provide these automatically when our 2022 vehicle was purchased? These details need to be made know to consumers because the time and money spent for tire replacement on these vehicles is considerable and we are averaging having to deal with this once a year so far.

The contact owns a 2022 Mercedes-Benz C300. The contact stated while driving at unknown speeds, the active brake assist was not functioning properly. The brakes were applied without an object around the vehicle. There were no warning lights illuminated. The local dealer was contacted and scheduled an appointment. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 20,000.