Home · 2020 Mercedes-benz C-class Cabriolet · Complaints

What 45 owners told NHTSA about the 2020 Mercedes-benz C-class Cabriolet

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (45)Crash / fire / injury (6)Engine (9)Transmission & drivetrain (7)Backup camera & sensors (4)Body & structure (4)Electrical system (4)Fuel system (4)Airbags (3)Driver assistance (3)Steering (3)Visibility & wipers (3)

3 of 45 complaints match · Visibility & wipers · clear filters

Aug 4, 2025Body & structureVisibility & wipers

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 ODI 11678311

Mar 11, 2025Visibility & wipers

Sunroof is not closing

NHTSA ODI 11647724

Jun 13, 2023Visibility & wipers

The contact owns a 2020 Mercedes-Benz C300. The contact stated while driving 55 MPH, the sunroof exploded without impact and glass fragments fell inside on the rear seats of the vehicle. The vehicle was taken to the dealer and the contact was informed that the sunroof needed to be replaced. The vehicle was not repaired. The contact stated that the failure had occurred twice. The manufacturer was contacted and stated that the vehicle was not under recall. No further assistance was provided. The failure mileage was 34,000.

NHTSA ODI 11526868

Working with the data? Download all 45 complaints as CSV · fetched from NHTSA July 14, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2020 Mercedes-benz C-class Cabriolet verdict →