2016 Mercedes-Benz B-Class — MOT failures & pass rate
30,367 MOT tests on the 2016 Mercedes-Benz B-Class are in this dataset, and 87.8% of them passed. That is 3.1 percentage points better than MPVs of a similar age, which fail at 15.3%. Failures cluster in tyres, lighting & signalling and suspension.
What the MOT record shows
No single area dominates — tyres (5.9%) and lighting & signalling (4.2%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are registration plate lamp(s), headlamp aim and coil spring — registration plate lamp(s) alone was recorded 925 times.
Condition tracks the odometer closely. Failures run at 8.1% in the 0-30k band and 19.9% in the 150k+ band, a 11.8-point spread — more than double.
The petrol cars hold up better: 10.2% fail against 12.8% for electric, a 2.6-point gap across 5,840 tests.
Tyres is the most common advisory, noted on 25.4% of tests — work that passed today but is likely due soon.
The trend is worsening — 8.8% of tests failed in 2021 against 15.1% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.9% | 1,791 |
| 2 | Lighting & signalling | 4.2% | 1,276 |
| 3 | Suspension | 2.7% | 822 |
| 4 | Brakes | 1.7% | 528 |
| 5 | Visibility | 1.6% | 499 |
| 6 | Emissions & environmental | 1.2% | 364 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Registration plate lamp(s) | 925 |
| 2 | Headlamp aim | 474 |
| 3 | Coil spring | 473 |
| 4 | Brake pads | 443 |
| 5 | Tread depth | 400 |
| 6 | Malfunction indicator lamp | 354 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 25.4% | 7,715 |
| 2 | Brakes | 14.5% | 4,396 |
| 3 | Other defects | 6.3% | 1,906 |
| 4 | Suspension | 3.7% | 1,110 |
| 5 | Visibility | 3.0% | 904 |
| 6 | Lighting & signalling | 2.3% | 691 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 7,149 | 8.1% |
| 30-60k | 14,722 | 11.5% |
| 60-90k | 6,296 | 15.6% |
| 90-120k | 1,637 | 19.7% |
| 120-150k | 402 | 21.6% |
| 150k+ | 156 | 19.9% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 24,527 | 12.5% |
| Petrol | 4,609 | 10.2% |
| Electric | 1,231 | 12.8% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 5,868 | 8.8% |
| 2022 | 5,983 | 10.7% |
| 2023 | 6,082 | 11.9% |
| 2024 | 6,182 | 14.2% |
| 2025 | 6,252 | 15.1% |
What to check before buying a 2016 B-Class
The failure pattern for this year is specific enough to inspect against: tyres accounted for 5.9% of tests. Start there.
- Tyres (5.9% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Lighting & signalling (4.2% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (2.7% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2016 Mercedes-Benz B-Classs pass their MOT?
87.8% of the 30,367 2016 Mercedes-Benz B-Class MOT tests in this dataset passed — a 12.2% fail rate.
What is the most common MOT failure on a 2016 Mercedes-Benz B-Class?
Tyres, recorded in 5.9% of tests, followed by lighting & signalling (4.2%).
Does the 2016 B-Class get worse with mileage?
Its MOT fail rate rises from 8.1% in the 0-30k band to 19.9% in the 150k+ band.
Methodology & source. Based on 30,367 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.