AI DamageMercedes-Benz C400: problems, complaints, bulletins
Summary for the Mercedes-Benz C400 across 1 model years: 10 owner complaints and 0 NHTSA service bulletins, plus repair videos. Pick a year for details.
Model years
| Year | Owner complaints | involving a crash | Technical service bulletins (TSB) | YouTube repair videos |
|---|---|---|---|---|
| 2015 | 10 | 0 | 0 | 0 |
What fails most often
- 1 Structure 60% of all complaints
- 2 Electrical system 10% of all complaints
- 3 Electronic stability control 10% of all complaints
- 4 Engine 10% of all complaints
- 5 Suspension 10% of all complaints
- 6 Vehicle speed control 10% of all complaints
- 7 Visibility 10% of all complaints
- Structure: 6 complaints (60% of all).
- Electrical system: 1 complaints (10% of all).
- Electronic stability control: 1 complaints (10% of all).
- Engine: 1 complaints (10% of all).
- Suspension: 1 complaints (10% of all).
Symptoms owners describe
How many of the 10 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Structure | 6 | 0 | 0 |
| Electrical system | 1 | 0 | 0 |
| Electronic stability control | 1 | 0 | 0 |
| Engine | 1 | 0 | 0 |
| Suspension | 1 | 0 | 0 |
| Vehicle speed control | 1 | 0 | 0 |
| Visibility | 1 | 0 | 0 |
| Other | 1 | 0 | 0 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
Rear subframe cracked while driving and rear of car sways from one lane to the next when brakes are applied. Car is not safe
My boyfriend and I were driving my 2015 MB C400 down the road in November 2020 and it was a beautiful day out so we decided we would open the sunroof to get some fresh air. I was driving so my boyfriend pressed the button for the sunroof to open.
My car failed PA State inspection due to a hole and rusted rear subframe. I have determined that there is a recall associated with this issue but that my vehicle just missed the recall limit. The recall affected 2008-2015 models (C Class with chassis 204). My vehicle is a 2015 C Class with chassis 205.
Panoramic glaaa sunroof mounting bracket made of cheap thin plastic that it breaks easily allowing the panoramic glass roof to fly off the car if driven while open.
Engine randomly stalls after sitting at red light/or while in traffic. All warning/dashboard lights come on and you can only start the car by putting it in park, then pushing start. The car has less than 10k miles. Dealership can't find code or replicate the issue.
While driving the vehicle on the highway at 70 mph, the cruise control shut off and the car began to slow down. I was able to maintain control and noticed 3 error messages including: esc inoperable, cruise control inoperable, and collision prevention plus inoperable.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
What to check before buying
- Structure. Rails, pillars, panel gaps, signs of pulling or welding.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Electronic stability control. ABS/ESC sensors, steering angle, codes after suspension repair.
- Engine. Cold start, unusual noises, oil leaks and engine codes.
Other models of this make
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.