2021 Mercedes-Benz C300 Problems, Recalls & Reliability
Verdict
BestComplaint Index
7/100
#15 most-complained of 16 C300 years
The 2021 Mercedes-Benz C300 has a complaint index of 7, ranking 15th out of 16 model years and earning a 'Best' verdict. It has 14 complaints, 7 recalls, and no reported crashes, fires, injuries, or deaths.
- Complaints
- 14
- Recalls
- 7
- Crashes / fires
- 0 / 0
- Injuries / deaths
- 0 / 0
- NHTSA overall rating
- Not rated
- EPA combined MPG
- 26.5
- 23 city / 32.5 hwy
Top 2021 Mercedes-Benz C300 problems
NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.
- Engine8 (57%)
- Fuel System3 (21%)
- Airbags1 (7%)
- Electrical System1 (7%)
- Collision Avoidance & Cameras1 (7%)
- Transmission & Powertrain1 (7%)
- Visibility & Wipers1 (7%)
What owners report
- Owners report engine failures including a broken piston connecting rod that damaged the engine block.
- Some describe cylinder head failures on the M264 engine, in one case at 35,000 miles and in another around 42,000 miles, often after the factory warranty expired.
- A pressure sensor upstream of the turbocharger short-circuited due to a kinked wire, triggering a check engine light.
- Fuel system complaints describe sudden loss of power and rough running on the highway, with one case involving a fuel injection failure diagnosed at 60,000 miles.
- One owner reported a coolant hose leak and a burning odor with an illuminated passenger airbag warning light.
- A panoramic sunroof was reported to malfunction with grinding or popping noises and failure to open or close.
2021 Mercedes-Benz C300 recalls
7 NHTSA recall campaigns list this model year.
- NHTSA 23V445000Jun 26, 2023Fuel System143,551 vehicles
Fuel system, gasoline:delivery:fuel pump
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021-2023 C-Class, E-Class, S-Class, CLS, SL, GT, GLC, GLE, GLS, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle details. The fuel pump may shutdown, which can result in a loss of drive power.
Risk: A loss of drive power can increase the risk of a crash.
Remedy: Dealers will replace the fuel pump, free of charge. Owner notification letters were mailed on June 14, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2023070012.
- NHTSA 22V365000May 20, 2022Electrical System242,722 vehiclesOver-the-air fix
Electrical system:software
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2022 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, AMG GT-Class, C-Class, E-Class, S-Class, SL-Class, GLC-Class, CLS-Class, GLB-Class, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. An error in the communication module's SIM card software can cause a mobile network connection failure, disabling the emergency call (eCall) system.
Risk: A disabled eCall system would prevent a vehicle occupant from contacting the emergency services call center in an emergency, potentially delaying emergency responders and increasing the risk of injury.
Remedy: The communication module software will be updated through an Over-the-Air (OTA) update or by a dealer, free of charge. Owner notification letters were mailed July 8, 2022. Owner notification letters will be mailed in phases, on July 8, 2022, May 17, 2024, July 29, 2024, and September 27, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's numbers are for this recall is 2022060005 and 2023110006.
- NHTSA 22V232000Apr 8, 2022Collision Avoidance & Cameras126,443 vehicles
Back over prevention:display function
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018-2021 CLA-Class, GLE/GLS-Class, A-Class, C-Class, E-Class, E-Class Coupe/Convertible, GLA/GLB-Class, GLC-Class, and CLS-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The rearview camera may not display the rearview image due to a software error. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 111, "Rear Visibility."
Risk: An inoperable rearview camera display reduces the driver's rear view, increasing the risk of a crash.
Remedy: Dealers will update the rearview camera software, free of charge. Owner notification letters were mailed July 15, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022060007.
2021 Mercedes-Benz C300 fuel economy and fuel cost
- City
- 23 MPG
- Highway
- 32.5 MPG
- Combined
- 26.5 MPG
- Annual fuel cost (EPA)
- $3,000
- 15,000 mi/yr
- Fuel
- Premium
- Current regular gas
- $4.32/gal
- national avg.
EPA figures; median across configurations of this model year. Estimate your own cost with the fuel cost calculator.
2021 compared with other C300 years
Frequently asked questions
- Is the 2021 Mercedes-Benz C300 reliable?
- Based on NHTSA owner complaints and recalls, the 2021 C300 has a complaint index of 7, the second-lowest among 16 model years, and carries a 'Best' verdict relative to other C300 years.
- What problems does the 2021 Mercedes-Benz C300 have?
- NHTSA lists 14 complaints for the 2021 C300, with Engine issues making up 57% of them, followed by Fuel System complaints at 21%. The median mileage at failure across all reported problems is 86,078.
- Does the 2021 Mercedes-Benz C300 have any recalls?
- NHTSA lists 7 recalls for the 2021 C300, covering fuel system, electrical system, collision avoidance cameras, structure/body, and seat belts. None are do-not-drive recalls.
- How does the 2021 C300 compare to other C300 model years?
- The 2021 C300 ranks 15th worst out of 16 model years with a complaint index of 7, well below higher-complaint years like 2011 (index 100) and 2010 (index 93).