2021 Mercedes-Benz C 300 problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
14 owner complaints analyzed
7 distinct recall campaigns
86,078 mi median reported failure mileage
Scope: 2021 model year. Data snapshot: . 3 complaints include usable failure mileage.
Most common problems
Engine is the most frequently named component, appearing in 8 of 14 complaints (57.1%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Electrical and battery issues | 3 | 21.4% |
| Transmission and shifting | 1 | 7.1% |
| Engine operation | 1 | 7.1% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Engine | 8 |
| Fuel/Propulsion System | 2 |
| Air Bags | 1 |
| Back Over Prevention: Sensing System: Camera | 1 |
| Electrical System | 1 |
| Fuel System, Gasoline | 1 |
| Power Train | 1 |
| Visibility:Sun/Moon Roof Assembly | 1 |
Engine: 8; Fuel/Propulsion System: 2; Air Bags: 1; Back Over Prevention: Sensing System: Camera: 1; Electrical System: 1; Fuel System, Gasoline: 1; Power Train: 1; Visibility:Sun/Moon Roof Assembly: 1
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 0 |
| 25,000 to 49,999 | 0 |
| 50,000 to 74,999 | 1 |
| 75,000 to 99,999 | 2 |
| 100,000 to 149,999 | 0 |
| 150,000 and above | 0 |
Under 25,000: 0; 25,000 to 49,999: 0; 50,000 to 74,999: 1; 75,000 to 99,999: 2; 100,000 to 149,999: 0; 150,000 and above: 0
75,000 to 99,999 miles has the most reports with usable mileage (2). 11 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2022 | 1 |
| 2023 | 1 |
| 2024 | 3 |
| 2025 | 6 |
| 2026 | 3 |
2022: 1; 2023: 1; 2024: 3; 2025: 6; 2026: 3
Pattern summary
Engine leads the component reports. Electrical and battery issues appears in 3 complaint narratives. Transmission and shifting appears in 1 complaint narratives. Engine operation appears in 1 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Complaint evidence
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11568290 · 2024-01-28 (January 28, 2024)
First day leasing the vehicle within 6 hours lights malfunction and malfunction warning on dash to seek workshop, vehicle was taken for inspection to original dealer (Mercedes Benz of Bakersfield). During inspection I added additional concerning complaints about passenger door not closing correctly/wind noise seeping through when closed, and hood not closing promptly. One month into leasing vehicle passenger window malfunction, took for inspection and repair to original dealer (MBofBakersfield). Concerned with caution for me, my family, and fr…
Owner-reported narrative. Look up ODI 11568290 at NHTSA ↗
Owner report 11579561 · 2024-03-26 (March 26, 2024)
the check Engine light fault code P012D12 The pressure sensor upstream of the turbocharger had a short circuit to positive. Found Kink wire on upstream pressure sensor. A short circuit to positive. Electrical Wire replaced.
Owner-reported narrative. Look up ODI 11579561 at NHTSA ↗
Owner report 11623522 · 2024-11-04 (November 4, 2024)
Rearview camera not displaying any image when transmission is put in reverse.
Owner-reported narrative. Look up ODI 11623522 at NHTSA ↗
Owner report 11706514 · 2025-12-22 (December 22, 2025)
The contact owns a 2021 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the vehicle stalled and failed to exceed 30 MPH, with the check engine warning light illuminated. The vehicle did not require a restart. The contact also stated that while stopped at a traffic light, the vehicle was shaking abnormally. The vehicle was taken to an independent mechanic, where it was diagnosed and determined that there was a misfire in cylinder #2. The contact was informed that the cylinder head needed to be replaced. The veh…
Owner-reported narrative. 86,078 miles reported. Look up ODI 11706514 at NHTSA ↗