Does the Mercedes-Benz B-Class fail the MOT on seat belts and airbags more than it should?
The Mercedes-Benz B-Class records 1.20 seat belts and airbags failure items per 100 initial MOT tests (2019–2024), against 0.86 expected for a car of the same age mix: about as expected for its class and age (the difference is within its interval or under 0.5 items per 100 tests) (+0.34, 95% interval +0.31 to +0.38). It ranks 173 of 627 models on seat belts and airbags (1 = most failures above expected).
Data release dvsa-2024-v2 (24 Sep 2026) · page updated 30 Sep 2026 · all models on seat belts and airbags · check a Mercedes-Benz B-Class by registration
What exactly fails on seat belts and airbags?
The most frequent DVSA defect wording in this group on the Mercedes-Benz B-Class is “An SRS malfunction indicator lamp (MIL) indicates a system malfunction”, recorded 3,048 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| An SRS malfunction indicator lamp (MIL) indicates a system malfunction | 3,048 | 0.78 |
| Seat belt buckle missing, damaged or not functioning as intended | 715 | 0.18 |
| Seat belt retractor not functioning as intended | 271 | 0.07 |
| Seat belt not functioning as intended or of an incorrect type | 239 | 0.06 |
| An airbag obviously inoperative | 155 | 0.04 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 391,293 (initial tests) · Method: failure items (major and minor) grouped by DVSA's defect tree; wordings with 30+ items · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
If a Mercedes-Benz B-Class gets a seat belts and airbags advisory, how often does it fail next time?
4.1% of Mercedes-Benz B-Class MOTs with a seat belts and airbags advisory were followed by a fail in the same group at the next MOT, typically 12.1 months and 6,244 miles later (1,509 advisories followed).
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 1,509 (advisories followed) · Method: the same vehicles followed to their next ordinary MOT · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
Other pages for this model
Mercedes-Benz B-Class 2005 · Mercedes-Benz B-Class 2006 · Mercedes-Benz B-Class 2007 · Mercedes-Benz B-Class 2008 · Mercedes-Benz B-Class 2009 · Mercedes-Benz B-Class 2010 · Mercedes-Benz B-Class 2011 · Mercedes-Benz B-Class 2012 · Mercedes-Benz B-Class 2013 · Mercedes-Benz B-Class 2014 · Mercedes-Benz B-Class 2015 · Mercedes-Benz B-Class 2016 · Mercedes-Benz B-Class 2017 · Mercedes-Benz B-Class 2018 · Mercedes-Benz B-Class 2019 · Mercedes-Benz B-Class 2020 · Mercedes-Benz B-Class in Norway · Mercedes-Benz B-Class in Finland · Mercedes-Benz B-Class in the Netherlands · Mercedes-Benz B-Class by postcode area · Mercedes-Benz B-Class body, chassis and structure failures · Mercedes-Benz B-Class brakes failures · Mercedes-Benz B-Class vehicle identification failures · Mercedes-Benz B-Class lamps, reflectors and electrics failures · Mercedes-Benz B-Class noise, emissions and leaks failures · Mercedes-Benz B-Class road wheels failures · Mercedes-Benz B-Class steering failures · Mercedes-Benz B-Class suspension failures · Mercedes-Benz B-Class tyres failures · Mercedes-Benz B-Class visibility failures