The Mercedes-Benz C-Class, a popular luxury sedan, underwent design changes for the 2008 model year. Significant safety enhancements were introduced over the years, including a driver’s knee airbag in 2010 to improve frontal crash protection. This article focuses on the safety performance of the 2014 Mercedes-Benz C 250, specifically in the challenging small overlap frontal crash test conducted by the Insurance Institute for Highway Safety (IIHS). Notably, for models built after December 2012, Mercedes-Benz reprogrammed the side curtain airbags to deploy in small overlap frontal crashes, aiming to further enhance occupant safety.
Understanding the IIHS Small Overlap Frontal Test
The IIHS small overlap frontal test is designed to simulate what happens when the front corner of a vehicle collides with an object like a tree or utility pole. This test is particularly demanding because it bypasses the main energy-absorbing structures of the vehicle’s front end. It’s a critical evaluation of how well a car protects its occupants in a severe, real-world crash scenario.
To assess the 2014 Mercedes-Benz C 250, the IIHS conducted two tests. The first test involved a 2012 model, while the second used a 2013 model manufactured after the crucial airbag reprogramming in December 2012. In the initial test, the driver’s side curtain airbag did not deploy as intended. However, in the subsequent test of the 2013 model, the side curtain airbag deployed correctly, demonstrating the effectiveness of the safety update. The official safety ratings and specifications are based on this second, more representative test. Although the vehicle’s structure remained unchanged, the structural rating considers data from both tests to provide a comprehensive evaluation.
Key Safety Ratings for the 2014 Mercedes-Benz C 250
The table below summarizes the safety ratings for the 2014 Mercedes-Benz C 250 in the small overlap frontal crash test:
| Evaluation criteria | Rating |
|---|---|
| Structure and safety cage | Acceptable |
| Driver injury measures | |
| Head/neck | Good |
| Chest | Good |
| Hip/thigh | Good |
| Lower leg/foot | Poor |
| Driver restraints and dummy kinematics | Good |
Action shot taken during the second of two small overlap frontal crash tests.
The 2014 Mercedes-Benz C 250 achieved “Good” ratings for driver injury measures concerning the head, neck, chest, and hip/thigh. This indicates a strong level of protection for these critical body regions. The “Good” rating for driver restraints and dummy kinematics further suggests that the seatbelt and airbag systems effectively controlled the dummy’s movement during the crash, minimizing potential injuries. However, the “Acceptable” rating for structure and safety cage, and the “Poor” rating for lower leg/foot injury, highlight areas of concern.
The dummy’s position in relation to the door frame, steering wheel, and instrument panel after the crash test, together with the footwell intrusion, indicates that the driver’s survival space wasn’t maintained well (second test shown).
Detailed Injury Measures and Footwell Intrusion
Technical measurements from the crash tests provide a deeper understanding of the injury risks. Significant footwell intrusion was observed in both tests of the 2014 Mercedes-Benz C 250.
| Measures of occupant compartment intrusion on driver side | Measurement (Test ID: CEN1327) |
|---|---|
| Lower occupant compartment | |
| Lower hinge pillar max (cm) | 12 |
| Footrest (cm) | 50 |
| Left toepan (cm) | 29 |
| Brake pedal (cm) | 22 |
| Parking brake (cm) | 20 |
| Rocker panel lateral average (cm) | 1 |
| Upper occupant compartment | |
| Steering column | 4 |
| Upper hinge pillar max (cm) | 11 |
| Upper dash (cm) | 10 |
| Lower instrument panel (cm) | 11 |
These measurements reveal substantial intrusion into the driver’s footwell area. For instance, the footrest intrusion measured a significant 50 cm in test CEN1327. This level of intrusion directly correlates with the “Poor” rating for lower leg/foot injury.
In the second test, the frontal and side curtain airbags worked well together to keep the head from coming close to any stiff structure or outside objects that could cause injury.
Despite the footwell intrusion concerns, the airbags performed effectively in protecting the head and upper body.
| Driver injury measures | Measurement (Test ID: CEN1327) |
|---|---|
| Head | |
| HIC-15 | 248 |
| Peak gs at hard contact | no contact |
| Neck | |
| Tension (kN) | 0.8 |
| Extension bending moment (Nm) | 9 |
| Maximum Nij | 0.15 |
| Chest maximum compression (mm) | 20 |
| Femur (kN) | |
| Left | 4.9 |
| Right | 3.2 |
| Knee displacement (mm) | |
| Left | 3 |
| Right | 3 |
| Knee-thigh-hip injury risk (%) | |
| Left | 3 |
| Right | 1 |
| Maximum tibia index | |
| Left | 2.14 |
| Right | 1.13 |
| Tibia axial force (kN) | |
| Left | 10.6 |
| Right | 4.1 |
| Foot acceleration (g) | |
| Left | 147 |
| Right | 98 |
The Head Injury Criterion (HIC) of 248 is well below the threshold for concern, and there was no hard contact detected for the head. Chest compression was also minimal at 20mm. However, the tibia index for the left lower leg was relatively high at 2.14, reinforcing the risk of lower leg injuries due to footwell intrusion.
In both tests, intrusion into the driver footwell was extensive and contributed to a high risk of injury to the left lower leg and at least a significant risk to the right lower leg. Also in both tests, the dummy’s right foot was trapped by intruding structure and the brake pedal as the left front wheel was forced rearward and inward during the crash (second test shown).
Conclusion: Balancing Safety in the 2014 Mercedes-Benz C 250
Overall, the 2014 Mercedes-Benz C 250 demonstrates good occupant protection in many aspects of the small overlap frontal crash, particularly for the head, neck, chest, and hip/thigh areas, thanks to effective airbag deployment and restraint systems. However, the significant footwell intrusion poses a notable risk of lower leg injuries. Prospective buyers should consider these findings when evaluating the overall safety of the 2014 Mercedes-Benz C 250. While the upper body protection is commendable, the lower leg injury risk remains a point of concern based on the IIHS small overlap frontal crash test results.
