NHTSA lists 1 complaints for the 2021 Mercedes-Benz C 300 4MATIC, 0 of them mention a crash and 0 mention a fire. 0 complaints mention an injury, with 0 injuries and 0 deaths reported.
Data build 2026-10-09.
NHTSA lists this vehicle as MERCEDES-BENZ C 300 4MATIC.
Complaints per 100k sold unavailable. No sales source is available for this record.
| System | Complaints | Share of this vehicle's complaints |
|---|---|---|
| AIR BAGS | 1 | 100.0% |
| POWER TRAIN | 1 | 100.0% |
| SUSPENSION | 1 | 100.0% |
| System | Subsystem | Complaints |
|---|
One complaint can name several systems, so shares can add to more than 100 percent.
These labels are model-generated, not NHTSA data.
| Label | Count | Share of tagged | Mean confidence |
|---|---|---|---|
| loss of control | 1 | 100.0% | 0.34 |
| Label | Count | Share of tagged | Mean confidence |
|---|---|---|---|
| high | 1 | 100.0% | 0.95 |
Model: typesafe/jev-1.13-20260917; schema version: tag-v1. 1 tagged complaints of 1 complaints (100.0%).
Confidence is the model's own probability for the label it chose (0 to 1), not accuracy.
Model-generated labels on tagged complaints only. Model years 2013 and newer are tagged in full; 2012 in part (see tagged_share); earlier model years have no tags. NHTSA's own flags remain separate in the complaints block.
See new recalls and investigations this week.
0 recalls.
0 investigations; 0 open.
48 manufacturer communications.
| System | Count |
|---|---|
| ELECTRICAL SYSTEM | 16 |
| POWER TRAIN | 12 |
| ENGINE | 7 |
| VISIBILITY/WIPER | 5 |
| STRUCTURE | 4 |
| UNKNOWN OR OTHER | 3 |
| EXTERIOR LIGHTING | 2 |
| FUEL/PROPULSION SYSTEM | 2 |
Date: 2026-09-26. Type: Service Bulletin/Repair Instructions. Systems: POWER TRAIN.
Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic /9Ga TRONIC automatic transmission) and 725.1 (NAG3 facelift/9Ga TRONIC automatic transmission facelift) For faster, more effective and more targeted diagnosis, Intelligent Predictive Repair (IPR) has been develop
Date: 2026-09-26. Type: Service Bulletin/Repair Instructions. Systems: STEERING.
Complaint Slight creaking noises when steering. Cause Noises may come from one or more sleeves of the horn contact plate. Remedy Remove the horn contact plate and check the sleeves for noise; see attached video. If necessary, apply lubricant to the sleeves.
Date: 2026-09-25. Type: Service Bulletin/Repair Instructions. Systems: VISIBILITY/WIPER.
Complaint CEL illuminates and/or AC does not blow cold. Cause Potentially relevance to hardware and/or software Remedy Scenario 1: 1. If the AC does not blow cold air, replace compressor (if compressor's index and part number Figure 1 match against Table 1). a. If the compressor does not fall within
Date: 2026-09-22. Type: Service Bulletin/Repair Instructions. Systems: SERVICE BRAKES.
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 vibra
Date: 2026-09-14. Type: Service Bulletin/Repair Instructions. Systems: POWER TRAIN.
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 Modified oil qu
Date: 2026-09-04. Type: Service Bulletin/Repair Instructions. Systems: POWER TRAIN.
Complaint Customer complaints relating to automatic transmission 725.0 (NAG3 Classic / 9Ga TRONIC automatic transmission) and 725.1 (NAG3 facelift/9Ga TRONIC automatic transmission facelift) For faster, more effective and more targeted diagnosis, Intelligent Predictive Repair (IPR) has been develo
Date: 2026-08-28. Type: Service Bulletin/Repair Instructions. Systems: STEERING.
Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR i??Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or contro
Date: 2026-08-24. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM, STRUCTURE.
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 that the tailgate no longer opens as a res
Date: 2026-08-15. Type: Warranty Program/Extension. Systems: FUEL/PROPULSION SYSTEM.
Dear Mercedes-Benz Owner: In our continuing efforts to ensure the proper performance of Mercedes-Benz products and to enhance the satisfaction of our customers, Mercedes-Benz USA is extending the warranty coverage for the Diagnostic Module for Tank Leakage Detection ("DMTL") on your vehicle from the
Date: 2026-08-12. Type: Service Bulletin/Repair Instructions. Systems: ELECTRICAL SYSTEM.
Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5. Cameras 6. Other Park Topics. Cause Various root causes Remedy See attached diagnostic guide.
None listed.
| NHTSA model label | Complaints |
|---|---|
| C 300 4MATIC | 1 |
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