At a glance
What can fail
This page covers 8 recalls and 10 owner complaints for the 2015 Mercedes-Benz C400.
Structure complaints dominate the 2015 Mercedes-Benz C400 owner reports. The most recurring issue involves the rear subframe, with multiple owners describing cracking or failure that causes the rear of the vehicle to sway or feel unstable, particularly when braking. A few owners say the problem was only discovered during routine service, while at least one describes noticeable handling instability before any diagnosis. Separately, owners report problems with the roof panel and sunroof area, including a front roof panel that separated while driving, water intrusion through the roof near the windshield during a car wash, and cracking or popping sounds when operating the sunroof. Engine and suspension each appear in single reports and don't show a clear pattern. The rear subframe concern is the most prominent thread across this complaint set.
10
Total Complaints
By System
The 2015 Mercedes-Benz C400 has 8 recalls, with the most serious concerns spanning a fuel system leak that can lead to fire, a driver airbag that can deploy without warning, and a steering shaft that can disengage and cause loss of steering control.
The fuel delivery module may not be properly secured to the tank and can leak fuel near potential ignition sources. The driver airbag can deploy unexpectedly, raising the risk of injury or a crash. A separate steering recall covers a sliding shaft that can separate from the steering coupling, producing noise and play in the wheel before potentially leaving the driver unable to steer. On the electric power steering side, a software fault in the steering control unit can cause power assist to cut out, requiring much greater effort to turn the wheel, particularly at low speeds. Two related recalls address roof panels that can detach from the vehicle and fall into traffic, with one covering panels that were not properly bonded during an earlier repair attempt. The emergency call system can send an incorrect timestamp that produces a wrong location during a crash call, which may slow emergency response. Headlights on certain vehicles have an adjustment mechanism that can misaim the low beam, either reducing road illumination or creating glare for oncoming drivers.
At a glance
What can fail
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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 →
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.
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
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
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.
At a glance
What can fail
The steering coupling interlock mechanism may not be locked, allowing the steering column's sliding shaft to separate from the coupling socket due to vibrations or road forces.
What the fix does
Dealers will inspect the steering coupling interlock mechanism and verify it is locked in the correct position at no cost.
Summarized — see the official notice for exact wording, dates, and contacts.