Mercedes-Benz B180 — MOT pass rate & failures
1,591 MOT tests on the Mercedes-Benz B180 (2009–2024) give an 89.4% pass rate. That is 7.7 percentage points better than the 18.2% fail rate across all Mercedes-Benz B-Class versions, so the B180 is a stronger pick within the range. Failures concentrate in lighting & signalling, tyres and suspension.
What the MOT record shows
At component level the recurring items are headlamp aim, tread depth and side repeaters — headlamp aim alone was recorded 31 times.
A 90-120k example is materially riskier than a 0-30k one: 29.1% versus 4.3%.
Tyres is the most common advisory, noted on 18.4% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 23.7% in 2021 to 7.6% in 2025, as the worst-kept examples leave the fleet.
How it compares
By model year
| Year | Tests | Pass rate | Fail rate |
|---|---|---|---|
| 2009 | 116 | 75.0% | 25.0% |
| 2010 | 167 | 73.7% | 26.4% |
| 2011 | 63 | 79.4% | 20.6% |
| 2012 | 129 | 86.8% | 13.2% |
| 2013 | 56 | 92.9% | 7.1% |
| 2014 | 31 | 96.8% | 3.2% |
| 2019 | 380 | 95.0% | 5.0% |
| 2020 | 268 | 94.8% | 5.2% |
| 2021 | 81 | 92.6% | 7.4% |
| 2022 | 230 | 93.9% | 6.1% |
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 4.5% | 71 |
| 2 | Tyres | 4.1% | 65 |
| 3 | Suspension | 2.5% | 40 |
| 4 | Brakes | 2.2% | 35 |
| 5 | Body, structure & corrosion | 1.5% | 24 |
| 6 | Visibility | 1.5% | 23 |
| 7 | Seat belts & restraints | 1.1% | 18 |
| 8 | Emissions & environmental | 0.9% | 14 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Headlamp aim | 31 |
| 2 | Tread depth | 22 |
| 3 | Side repeaters | 22 |
| 4 | Individual direction indicators | 22 |
| 5 | Joints | 18 |
| 6 | Coil spring | 17 |
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 | 18.4% | 293 |
| 2 | Brakes | 12.8% | 204 |
| 3 | Other defects | 7.3% | 116 |
| 4 | Suspension | 7.0% | 112 |
| 5 | Visibility | 3.8% | 60 |
| 6 | Lighting & signalling | 2.7% | 43 |
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 | 700 | 4.3% |
| 30-60k | 504 | 11.7% |
| 60-90k | 266 | 15.8% |
| 90-120k | 86 | 29.1% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 97 | 23.7% |
| 2022 | 202 | 14.8% |
| 2023 | 302 | 10.3% |
| 2024 | 396 | 9.8% |
| 2025 | 594 | 7.6% |
What to check before buying a Mercedes-Benz B180
Focus on the areas it most often fails on — and remember MOT data covers testable defects only, not engine or gearbox health.
- Lighting & signalling (4.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Tyres (4.1% 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.
- Suspension (2.5% 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 reliable is the Mercedes-Benz B180 at MOT time?
89.4% of the 1,591 Mercedes-Benz B180 MOT tests in this dataset passed — a 10.6% fail rate, better than the 18.2% average across all B-Class versions.
What is the most common MOT failure on a Mercedes-Benz B180?
Lighting & signalling, recorded in 4.5% of tests, followed by tyres (4.1%).
Does the B180 get worse with mileage?
Its MOT fail rate rises from 4.3% in the 0-30k band to 29.1% in the 90-120k band.
Methodology & source. Based on 1,591 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.