NHTSA (USA)High Risk
At a glance
What can fail
The front roof panel between the windshield and panoramic sunroof may have been improperly bonded during a prior repair, causing the panel to detach from the vehicle.
This page covers 10 recalls, 375 owner complaints and EPA fuel economy for the 2015 Mercedes-Benz C300.
28 mpg combined
8.4 L/100km
Compact Cars
Fuel economy data from fueleconomy.gov (EPA / U.S. Dept. of Energy). Annual cost based on 15,000 mi/yr at 55% city driving and current fuel prices. MPG is U.S. gallons; L/100km converted.
Engine complaints dominate the 2015 Mercedes-Benz C300 ownership picture, with owners frequently describing stalling, sputtering, and sudden loss of power while driving, sometimes at highway speeds, and sometimes with no prior warning light. A separate cluster of fuel system reports centers on fuel hose leaks, with owners noting a strong gasoline smell inside the cabin; a dealer-confirmed repair was described in more than one account. Structure complaints form the third-largest group, with two distinct patterns: moonroof panels detaching and flying off at speed, and rear subframe corrosion, rust progressing to the point of compromising chassis integrity and affecting handling. Some owners also report a lateral body shift under braking, though that appears in fewer accounts. The moonroof separation and fuel odor complaints appear across multiple reports rather than as isolated incidents.
375
Total Complaints
9
Crash-Related
1
Fire-Related
4
With Injuries
By System
The 2015 Mercedes-Benz C300 has 10 recalls, the most serious involving an airbag that can deploy without warning, a starter component that can overheat and melt surrounding parts causing a fire, and a fuel delivery module that can work loose and leak fuel near ignition sources.
The roof panel bonded between the windshield and panoramic sunroof can detach from the vehicle and become a road hazard, and this applies both to original production bonding and to vehicles where a prior repair attempt did not fully resolve the issue. On the steering side, a software error in the electric power steering control unit can cause a sudden loss of assist, requiring significantly more physical effort to steer, particularly at low speeds. A separate steering rack defect on rear-wheel drive models can also prevent proper steering control. Airbag software on certain vehicles may cause the system to fail to deploy in a crash. There is also a headlight aim issue where adjusting the low beams using the original horizontal setting can misdirect light away from the road or create excessive glare for oncoming drivers. The emergency call system carries a software fault that can report an incorrect vehicle location to emergency responders.
At a glance
What can fail
The front roof panel between the windshield and panoramic sunroof may have been improperly bonded during a prior repair, causing the panel to detach from the vehicle.
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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 →
What the fix does
Dealers will replace the front roof panel at no charge to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The front roof panel between the windshield and panoramic sunroof may not be properly bonded to the vehicle from a previous repair, risking separation.
What the fix does
The dealer will remove and replace the front roof panel using proper bonding materials and procedures at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error causes the eCall emergency system's date and time to be incorrect, which may result in an inaccurate vehicle location being sent during an emergency call.
What the fix does
Mercedes-Benz will send a remote software update to your vehicle. Dealers will verify the update worked or install a new communication module software at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A locknut in the steering rack may break under heavy load, potentially causing the steering to lock in one position.
What the fix does
Dealers will replace the steering rack at no cost to you.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The driver's airbag may deploy unexpectedly if the steering components lack proper grounding and the airbag clockspring is broken, allowing electrostatic discharge to trigger deployment.
What the fix does
Dealers will add grounding to the steering components to prevent electrostatic discharge from triggering the airbag.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
Control unit software may be incorrect, potentially preventing airbags from deploying properly during a crash.
What the fix does
Dealers will update the control unit software at no cost to restore proper airbag deployment function.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
When the engine or transmission won't start, the starter motor keeps trying to turn over. This repeated effort can cause the starting current limiter to overheat.
What the fix does
A dealer will install an additional fuse in the electrical line to the starter motor to protect against overheating.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
A software error in the electric power steering control unit may cause the power steering assist to stop working.
What the fix does
Dealers will update the power steering control software at no cost to restore proper steering assist.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The fuel delivery module may not be properly secured to the fuel tank. Electrical wires connecting to the module could be pinched between the module flange and tank.
What the fix does
Dealers will inspect locking plates and wires for damage or improper securing, then correct any issues found at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.
At a glance
What can fail
The headlamp horizontal adjustment mechanisms can be manually adjusted by owners instead of being sealed with caps, which doesn't comply with federal lamp safety standards.
What the fix does
Dealers will replace the headlamp adjustment mechanisms with proper sealing caps to meet safety requirements.
Summarized — see the official notice for exact wording, dates, and contacts.