Car Defect Radar
Built from NHTSA complaints and recalls collected for this model, generated September 22, 2026. Totals reflect what has been collected, not every complaint ever filed.

Recalls

0 total

Safety issues the manufacturer must repair for free. A recall means confirm the fix was done, not walk away.

No recalls on record for this model

No safety recalls were found in this dataset. It is still worth entering the exact VIN on NHTSA before purchase, since recalls can be added at any time.

Owner complaints by system

15 total

Unverified reports owners filed with NHTSA, grouped by the part of the car. Useful for spotting patterns. Open a group to read recent examples.

Engine & powertrain

Minor
10

Most reports here involve sudden stalling.

sudden stalling 3premature wear 2
A recent report: The contact owns a 2021 Mercedes-Benz C 300. The contact stated that while depressing the accelerator pedal, there was a loud knocking sound coming from the engine compartment while accelerating…
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The contact owns a 2021 Mercedes-Benz C 300. The contact stated that while depressing the accelerator pedal, there was a loud knocking sound coming from the engine compartment while accelerating. There were no warning lights illuminated. The vehicle was taken to the dealer to be diagnosed, and it was determined that the spawn rod was fractured, causing engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The contact stated that the engine was previously repaired because of the head gasket failure in 2024. The manufacturer was informed of the issue, and a case was opened. The failure mileage was approximately 88,000.

Source: NHTSA complaint ODI #11755408 · view all complaints for this vehicle at nhtsa.gov

Electrical & infotainment

Minor
2

Most reports here involve transmission slipping.

transmission slipping 1software faults 1
A recent report: Rearview camera not displaying any image when transmission is put in reverse.

Source: NHTSA complaint ODI #11623522 · view all complaints for this vehicle at nhtsa.gov

Steering, suspension & tires

Minor
1

Most reports here involve airbags deploying unexpectedly.

airbags deploying unexpectedly 1
A recent report: Driving and something came from underneath the vehicle and cause me to swerve in all the airbags deployed

Source: NHTSA complaint ODI #11704073 · view all complaints for this vehicle at nhtsa.gov

Airbags & seat belts

Minor
1

Most reports here involve electrical shorts.

electrical shorts 1
A recent report: The contact owns a 2021 Mercedes-Benz C300. The contact stated while driving at an unknown speed, there was a burning odor inside the vehicle. The contact stated the passenger side air bags was…
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The contact owns a 2021 Mercedes-Benz C300. The contact stated while driving at an unknown speed, there was a burning odor inside the vehicle. The contact stated the passenger side air bags was enabled warning light was illuminated. The contact also stated the vehicle made an abnormal noise. The contact took the vehicle to the local dealer but was unable to duplicate the failure. The manufacturer had not been informed of the failure. The failure mileage was unknown.

Source: NHTSA complaint ODI #11453645 · view all complaints for this vehicle at nhtsa.gov

Structure & body

Minor
1

Most reports here involve other issues.

other issues 1
A recent report: I am reporting a safety defect involving the panoramic sunroof on my 2021Mercedes-Benz Coop vehicle. The panoramic sunroof has malfunctioned due to an apparent design or manufacturing defect. The…
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I am reporting a safety defect involving the panoramic sunroof on my 2021Mercedes-Benz Coop vehicle. The panoramic sunroof has malfunctioned due to an apparent design or manufacturing defect. The sunroof fails to open / close and makes grinding or popping noises which malfunctioned unexpectedly. This issue occurred without misuse and during normal operation of the vehicle. The defect creates a safety concern because it can distract the driver, allow water intrusion that may affect electrical components, and/or cause sudden glass or mechanical failure while driving. The vehicle has been taken to a Mercedes-Benz dealership for diagnosis and the issue was not resolved due to denied coverage. I was informed that the repair would be costly despite the issue appearing to be a known defect in Mercedes-Benz panoramic sunroof systems. I believe this defect may affect other Mercedes-Benz vehicles with panoramic sunroofs and should be investigated for a potential safety defect or recall.

Source: NHTSA complaint ODI #11712287 · view all complaints for this vehicle at nhtsa.gov

Is 15 complaints a lot? They were filed between 2022 and 2026, roughly 3 a year, which is more than the typical model in this dataset. We do not have sales figures for this model, so treat this as a rough volume, not a rate per car on the road. Popular, high-volume models naturally collect more complaints over time.