2021 Mercedes-Benz C 300 problems, complaints & recalls

2021 Mercedes-Benz C 300 recalls (7)

• Recall 23V445000Jun 26, 2023143,551 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.

• Recall 22V365000May 20, 2022242,722 vehicles
  COMMUNICATION: AUTO CRASH NOTIFICATION · 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.

• Recall 22V232000Apr 8, 2022126,443 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.

• Recall 21V406000May 28, 2021218 vehicles
  SEATS:MID/REAR ASSEMBLY:HEAD RESTRAINT

  Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C300 Cabriolet, C43 AMG Cabriolet, C63 AMG Cabriolet, C63 AMG S Cabriolet, E450 Cabriolet, and E53 AMG Cabriolet vehicles. The rear headrests may be incorrectly mounted to the seatbacks.

  Risk: Incorrectly mounted headrests could move or detach from the seat during a crash, increasing the risk of injury.

  Remedy: Dealers will inspect the rear seatback guide bushings and replace them if necessary, free of charge. Owner notification letters were mailed July 16, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021060010.

• Recall 21V230000Apr 1, 20218,634 vehicles
  AIR BAGS:SENSOR:OCCUPANT CLASSIFICATION · SEAT BELTS:PRETENSIONER · SEATS

  Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021 C-Class, E-Class, E-Class Coupe and Convertible, GLC, CLS, AMG GT 4-door Coupe and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle model details. A faulty electrical contact within the seat position switch may prevent the driver and passenger air bags and seat belt force limiters from properly activating during a crash.

  Risk: Air bags and seat belts that do not perform properly in a crash can increase the risk of injury.

  Remedy: MBUSA will notify owners, and dealers will replace the seat position switches, free of charge. Owner letters were mailed May 21, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021040016.

• Recall 21V058000Feb 5, 20211,292,258 vehicles
  COMMUNICATION: AUTO CRASH NOTIFICATION · ELECTRICAL SYSTEM:SOFTWARE

  Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2016 - 2021 CLA-Class, GLA-Class, GLE-Class, GLS-Class, SLC-Class, A-Class, GT-Class, C-Class, E-Class, S-Class, CLS-Class, SL-Class, B-Class, GLB-Class, GLC-Class, and G-Class vehicles. Please refer to the Part 573 report for specific vehicle model details. The software design of the communication module may fail to communicate the correct vehicle location for the emergency call system (eCall) in the event of a crash.

  Risk: Failure of the eCall system may result in emergency responders being dispatched to the wrong location, increasing the risk of injury following a crash.

  Remedy: MBUSA will notify owners, and the communication module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. The recall began March 12, 2021. Owners may contact MBUSA customer service at 1-877-762-8267. MBUSA's number for this recall is 2021020025.

• Recall 21V032000Jan 29, 202124,550 vehicles
  SEAT BELTS:FRONT:RETRACTOR

  Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2021 C300, 2017-2020 AMG C43, and AMG C63 vehicles. The front seat belts might not fully retract to their stowed position. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 208, "Occupant Crash Protection."

  Risk: If the seat belt does not fully retract, the occupant may find the operation of the seat belt inconvenient and not wear it, increasing the risk of injury in the event of a crash.

  Remedy: MBUSA will notify owners, and dealers will check the retraction function of the front seat belts and adjust the damping foam within the B-pillars, as necessary, free of charge. The recall began February 26, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2021020010.

Recent 2021 Mercedes-Benz C 300 complaints

Excerpts of the newest owner complaints, lightly cleaned of personal details. Complaints are unverified owner reports.

1. Filed Aug 7, 202688,000 miWIEngine

   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…

   NHTSA complaint #11755408 · source
2. Filed May 19, 202660,000 miFLTowedFuel, Hybrid & EV Propulsion

   The contact owns a 2021 Mercedes Benz C. The contact stated that while driving on the highway, the vehicle began to lose power, riding rough. The check engine light illuminated. The vehicle was towed to the dealer where it was diagnosed with a fuel injection failure. The vehicle read diagnostic code P1CEF85. The manufacturer was made aware of the issue. The approximate failure mileage was 60,000.

   NHTSA complaint #11738727 · source
3. Filed Jan 20, 2026CAVisibility & Wipers

   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…

   NHTSA complaint #11712287 · source
4. Filed Dec 22, 202586,078 miNJEngine

   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…

   NHTSA complaint #11706514 · source
5. Filed Nov 25, 2025CAEngine

   2021 Mercedes-Benz C300 with M254 2.0L turbo engine experienced sudden cylinder head failure at 44,000 miles due to manufacturing porosity in the cylinder head and camshaft bore scoring. Dealer confirmed defect. This is a known, recurring issue on 2021–2023 M254 engines with multiple documented failures under 50k miles. Sudden loss of compression and misfires create a safety risk of engine failure or fire while driving. TSB NUMBER LI07.16-P-074000 (February 2023, updated…

   NHTSA complaint #11701560 · source
6. Filed Nov 25, 2025MSFuel, Hybrid & EV Propulsion

   My car had a coolant leak last year a hose broke and I have a 2021. My son’s mercedes sis the same thing on 11/23/2025. I have researched ma y others with this same issue. There should be a recall on that hose or whatever the problem Is.

   NHTSA complaint #11701496 · source
7. Filed Oct 6, 2025FLFuel, Hybrid & EV Propulsion

   While driving car on Sunday 10/5, it suddenly failed to respond to gas pedal pressure. The car stopped accelerating and rather slowed to 15 MPH, almost causing a car from behind to hit me in the rear side.

   NHTSA complaint #11691568 · source
8. Filed Aug 6, 2025MAEngineTransmission & Drivetrain

   My C300 only had about 42,000 miles and was less than 5 years old. Just after the factory warranty expired, the engine was running rough and hot, and "check engine" light illuminated. My local garage quickly diagnosed the problem as a failed cylinder head, stated that it is common with Mercedes 4-cylinder engines from about 2017, and said Mercedes may cover it since it is a "known problem" and shouldn't happen with that mileage. I was charged $7,860 by my local Mercedes…

   NHTSA complaint #11678865 · source

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Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data, as of Oct 11, 2026. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology