NHTSA (USA)Critical
At a glance
What can fail
The fuel pump may shut down unexpectedly, causing a loss of engine power while driving.
What the fix does
Dealers will replace the fuel pump at no cost to you.
This page covers 7 recalls and 12 owner complaints for the 2021 Mercedes-Benz C 300.
Engine complaints dominate what owners of the 2021 Mercedes-Benz C 300 report. The most common theme involves the 2.0-liter turbocharged engine losing power unexpectedly while driving, owners describe the vehicle failing to accelerate, slowing to very low speeds, and in some cases the check engine light coming on. A related pattern involves abnormal shaking or stalling, sometimes occurring at a stop. A smaller group of owners reports coolant system problems, specifically coolant leaks they attribute to hose failures. One owner describes a cylinder head failure with camshaft bore damage confirmed by a dealer at around 44,000 miles, though that remains an individual report rather than a clear pattern. Outside the engine and cooling system, a single complaint mentions the panoramic sunroof failing to open or close and producing grinding or popping noises during normal operation.
12
Total Complaints
By System
The 2021 Mercedes-Benz C 300 has 7 recalls, the most serious being a fuel pump that can shut down without warning, cutting drive power and raising the risk of a crash.
On the occupant protection side, a separate recall addresses airbags and seatbelt pretensioners that may not perform correctly in a crash. On Cabriolet trims, rear headrests may be incorrectly mounted and can move or detach during a crash. The front seatbelts may also fail to fully retract to their stowed position, which can make the belt awkward enough that some occupants choose not to wear it.
Two recalls cover the automatic crash notification system: a software fault can send emergency responders to the wrong location, and a separate issue can disable the system entirely so occupants cannot reach emergency services at all. There is also a rearview camera recall where a software error prevents the camera image from displaying when reversing, reducing rear visibility.
At a glance
What can fail
The fuel pump may shut down unexpectedly, causing a loss of engine power while driving.
What the fix does
Dealers will replace the fuel pump at no cost to you.
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Complaints are owner-reported and reflect individual experiences, not confirmed defects. They are distinct from recalls. Data sourced from the national vehicle safety complaint database. See trending complaints →
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error in the communication module's SIM card can prevent mobile network connection, which disables the emergency call (eCall) system.
What the fix does
The communication module software will be updated at no cost through an over-the-air update or by a dealer.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error prevents the rearview camera from displaying the backup image on the screen.
What the fix does
Dealers will update the rearview camera software at no cost to restore the backup image display.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The rear headrests may be incorrectly mounted to the seatbacks due to defective guide bushings.
What the fix does
Dealers will inspect the rear seatback guide bushings and replace them if necessary at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A faulty electrical contact in the seat position switch may prevent driver and passenger air bags and seat belt force limiters from activating during a crash.
What the fix does
Dealers will replace the seat position switches at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The communication module software may fail to send your vehicle's correct location to emergency services when the eCall system activates during a crash.
What the fix does
A dealer will update the communication module software, or the update will be sent over-the-air, at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The front seat belts may not fully retract back into their stowed position after use.
What the fix does
Dealers will check the front seat belt retraction and adjust the damping foam in the B-pillars as needed at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.