AI Damage2017 Mercedes-Benz C450: common problems
Owners of the 2017 Mercedes-Benz C450 filed 3 complaints with NHTSA, most often about visibility and wheels. The maker issued 120 service bulletins for this year. Details by component below, with sources.
Key figures
- Owner complaints
- 3
- Technical service bulletins (TSB)
- 120
What fails most often
- 1 Visibility 33% of all complaints
- 2 Wheels 33% of all complaints
- Visibility: 1 complaints (33% of all); manufacturer bulletins for this component: 9.
- Wheels: 1 complaints (33% of all); manufacturer bulletins for this component: 2.
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Visibility | 1 | 0 | 9 |
| Wheels | 1 | 0 | 2 |
| Electrical system | 0 | 0 | 40 |
| Powertrain | 0 | 0 | 24 |
| Equipment | 0 | 0 | 19 |
| Exterior lighting | 0 | 0 | 14 |
| Structure | 0 | 0 | 11 |
| Engine and cooling | 0 | 0 | 6 |
| Steering | 0 | 0 | 4 |
| Backover prevention | 0 | 0 | 2 |
| Engine | 0 | 0 | 2 |
| Fuel/propulsion system | 0 | 0 | 2 |
| Service brakes | 0 | 0 | 2 |
| Suspension | 0 | 0 | 2 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
- windshield, and I had Satellite repair it through an insurance claim because it was urgent for my safety. - the windshield and its adhesive never bonded together making the windshield structurally unsafe and if I would have gotten into an accident then my vehicles airbags would have not deployed properly.
5 months after recieveing the car I was on the highway and my front passanger side tire air presuure indicator went off. I pulled off the highway and put a "fix a flat" in the tire thinking I ran over a nail.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 17,152 of 36,659 model years in the NHTSA data (top 47% most complained about).
On average one model year of the C450 has 10 complaints (2 years in the data). This year has 3, below average.
What to check before buying
- Visibility. Wipers, mirrors, defrosters, cracked glass.
- Wheels. Wheel runout, cracks, signs of a wheel strike.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
Manufacturer service bulletins
Bulletin titles as filed with NHTSA.
- Complaint Clanking noise from the area of the speakers in the doors
Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and…
- Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic /9G‑TRONIC automatic…
Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic /9G‑TRONIC automatic transmission) and 725.1 (NAG3 facelift/9G‑TRONIC automatic transmission facelift) For faster, more effective and…
- Complaint Repeat workshop visit for vehicle vibration while braking from 60MPH. NOTE
Although the symptom is similar to a tire or wheel vibration, it is usually readily noticeable that it is distinctly different if it happens at all times or only while braking. Cause Although the cause of the vibration…
- Complaint Only vehicles with a variable transfer case are affected
This can be identified through control unit N45 or N15/7 in the quick test. When accelerating with light load, vibrations or jolting sensation may come from the drivetrain. It may be mistaken for a harsh shift. Cause…
- Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic / 9G‑TRONIC automatic…
Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic / 9G‑TRONIC automatic transmission) and 725.1 (NAG3 facelift/9G‑TRONIC automatic transmission facelift) For faster, more effective…
- Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same…
Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering…
- Complaint Tailgate opens unintentionally
Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket, handbag etc. Remedy As of the 6th generation, the vehicle key can be recoded so…
- Complaint A popup is seen on the HU with the message "data connection temporarily not available"
Potentially affected functionalities in NTG4.5, NTG5 1.Weather 2.Local Search 3.IP Radio 4.Send2Car 5.Speech Detection Service 6.Navigation 7.iHeartRadio 8.Traffic Cams Cause MB Apps is sundowned for all vehicles with…
- Complaint This document is intended as a pre-case diagnostic reference for transmission related concerns
It will also ensure that if a case is necessary, all supporting documentation is available. This should not be used on its own as justification for creating a TIPS case. Cause The root cause will vary depending on the…
- Complaint Mercedes-Benz USA is currently experiencing limited availability of transmission fluid…
Complaint Mercedes-Benz USA is currently experiencing limited availability of transmission fluid specification ATF 236.17 due to a global supply constraint. 236.17 ATF 1L and 5L (PNs: A002989060312 and A002989060313)…
- Complaint Crackling and cracking noise from the outer wheel on the front axle when cornering Cause The…
Complaint Crackling and cracking noise from the outer wheel on the front axle when cornering Cause The noise is generated by a micromovement on the contact surface between the rim and the brake disk (wheel bolt group)…
- Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end)
The noise is heard once in each instance when changing direction of travel. Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the…
NHTSA lists 120 bulletins for this year; the 12 newest are shown here.
Other years of this model
Questions and answers
What are the most common problems with the 2017 Mercedes-Benz C450?
Owner complaints to NHTSA most often mention: visibility, wheels. Total complaints: 3. The most frequent symptoms in complaint texts: windows, sunroof (33%).
How many service bulletins (TSB) were issued for the 2017 Mercedes-Benz C450?
NHTSA lists 120 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2017 Mercedes-Benz C450 from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2017 models
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.