BMW M135i — MOT pass rate & failures
26,547 MOT tests on the BMW M135i (2008–2024) give a 91.8% pass rate. That is 7.8 percentage points better than the 16.0% fail rate across all BMW 1 Series versions, so the M135i is a stronger pick within the range. Failures concentrate in tyres, lighting & signalling and brakes.
What the MOT record shows
At component level the recurring items are tread depth, brake pads and headlamp aim — tread depth alone was recorded 557 times.
Condition tracks the odometer closely. Failures run at 7.1% in the 0-30k band and 15.4% in the 90-120k band, a 8.3-point spread — more than double.
Tyres is the most common advisory, noted on 18.4% of tests — work that passed today but is likely due soon.
How it compares
By model year
| Year | Tests | Pass rate | Fail rate |
|---|---|---|---|
| 2013 | 93 | 88.2% | 11.8% |
| 2014 | 75 | 85.3% | 14.7% |
| 2015 | 116 | 87.9% | 12.1% |
| 2016 | 208 | 90.9% | 9.1% |
| 2019 | 4,060 | 90.6% | 9.4% |
| 2020 | 11,575 | 91.6% | 8.3% |
| 2021 | 7,565 | 92.3% | 7.7% |
| 2022 | 2,639 | 93.1% | 6.9% |
| 2023 | 176 | 96.6% | 3.4% |
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.9% | 1,571 |
| 2 | Lighting & signalling | 1.0% | 266 |
| 3 | Brakes | 0.9% | 237 |
| 4 | Visibility | 0.8% | 206 |
| 5 | Suspension | 0.5% | 144 |
| 6 | Other defects | 0.4% | 101 |
| 7 | Emissions & environmental | 0.2% | 65 |
| 8 | Road wheels | 0.2% | 52 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 557 |
| 2 | Brake pads | 232 |
| 3 | Headlamp aim | 200 |
| 4 | Registration plates | 159 |
| 5 | Wipers | 154 |
| 6 | Coil spring | 115 |
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% | 4,878 |
| 2 | Brakes | 8.4% | 2,228 |
| 3 | Other defects | 3.9% | 1,029 |
| 4 | Visibility | 1.9% | 515 |
| 5 | Suspension | 0.6% | 149 |
| 6 | Emissions & environmental | 0.4% | 115 |
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 | 15,539 | 7.1% |
| 30-60k | 10,032 | 9.4% |
| 60-90k | 861 | 13.2% |
| 90-120k | 91 | 15.4% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 96 | 9.4% |
| 2022 | 1,390 | 8.5% |
| 2023 | 5,288 | 7.9% |
| 2024 | 8,722 | 8.4% |
| 2025 | 11,051 | 8.1% |
What to check before buying a BMW M135i
Focus on the areas it most often fails on — and remember MOT data covers testable defects only, not engine or gearbox health.
- 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 (1.0% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (0.9% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
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 BMW M135i at MOT time?
91.8% of the 26,547 BMW M135i MOT tests in this dataset passed — a 8.2% fail rate, better than the 16.0% average across all 1 Series versions.
What is the most common MOT failure on a BMW M135i?
Tyres, recorded in 5.9% of tests, followed by lighting & signalling (1.0%).
Does the M135i get worse with mileage?
Its MOT fail rate rises from 7.1% in the 0-30k band to 15.4% in the 90-120k band.
Methodology & source. Based on 26,547 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.