Mazda B Series MOT pass rate & common failures
Across 40 model years and 12,201 tests, the Mazda B Series passes its MOT 72.4% of the time. That is effectively the same as all cars of a similar age (27.1% fail rate), so the MOT record here is unremarkable in either direction. Its most common failure areas are lighting & signalling, body, structure & corrosion and brakes.
What the MOT record shows
Lighting & signalling dominates the failure mix at 19.0% of all tests — 5.1 points clear of body, structure & corrosion, so it is the first thing to check.
At component level the recurring items are rear fog lamp, joints and rigid brake pipes — rear fog lamp alone was recorded 1,030 times.
Mileage is the strongest signal on the record: 15.4% of 0-30k cars fail, rising to 29.0% once past 150k.
Advisories point at the next bill rather than this one: brakes was flagged on 36.4% of tests without failing them.
The trend is improving — the fail rate fell from 28.9% in 2021 to 27.0% in 2025, as the worst-kept examples leave the fleet.
How it compares
By model year
Every B Series model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 1988 | 46 | 73.9% | 26.1% | Lighting & signalling |
| 1990 | 34 | 82.3% | 17.6% | Suspension |
| 1991 | 30 | 76.7% | 23.3% | Lighting & signalling |
| 1992 | 70 | 78.6% | 21.4% | Lighting & signalling |
| 1993 | 33 | 72.7% | 27.3% | Body, structure & corrosion |
| 1994 | 47 | 72.3% | 27.7% | Lighting & signalling |
| 1995 | 60 | 80.0% | 20.0% | Lighting & signalling |
| 1996 | 35 | 71.4% | 28.6% | Lighting & signalling |
| 1998 | 253 | 74.3% | 25.7% | Lighting & signalling |
| 1999 | 600 | 73.5% | 26.5% | Lighting & signalling |
| 2000 | 1,228 | 72.9% | 27.1% | Lighting & signalling |
| 2001 | 904 | 71.6% | 28.4% | Lighting & signalling |
| 2002 | 1,730 | 73.1% | 26.9% | Lighting & signalling |
| 2003 | 1,898 | 71.3% | 28.7% | Lighting & signalling |
| 2004 | 1,376 | 70.9% | 29.1% | Lighting & signalling |
| 2005 | 2,631 | 72.1% | 27.9% | Lighting & signalling |
| 2006 | 977 | 73.7% | 26.3% | Lighting & signalling |
| 2007 | 45 | 73.3% | 26.7% | Body, structure & corrosion |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 19.0% | 2,317 |
| 2 | Body, structure & corrosion | 13.9% | 1,690 |
| 3 | Brakes | 11.2% | 1,365 |
| 4 | Suspension | 10.9% | 1,325 |
| 5 | Visibility | 6.0% | 727 |
| 6 | Tyres | 3.3% | 406 |
| 7 | Emissions & environmental | 3.3% | 402 |
| 8 | Steering | 2.7% | 328 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Rear fog lamp | 1,030 |
| 2 | Joints | 913 |
| 3 | Rigid brake pipes | 860 |
| 4 | Chassis condition | 760 |
| 5 | Position lamp | 710 |
| 6 | Headlamp aim | 683 |
| 7 | Headlamp | 569 |
| 8 | Component mounting prescribed areas | 567 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 36.4% | 4,443 |
| 2 | Body, structure & corrosion | 32.1% | 3,918 |
| 3 | Suspension | 29.8% | 3,640 |
| 4 | Tyres | 19.9% | 2,427 |
| 5 | Lighting & signalling | 15.2% | 1,858 |
| 6 | Other defects | 15.1% | 1,840 |
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 | 162 | 15.4% |
| 30-60k | 995 | 20.4% |
| 60-90k | 2,179 | 25.8% |
| 90-120k | 3,174 | 29.8% |
| 120-150k | 2,786 | 28.0% |
| 150k+ | 2,878 | 29.0% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 11,896 | 27.8% |
| Petrol | 302 | 19.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 3,226 | 28.9% |
| 2022 | 2,755 | 27.0% |
| 2023 | 2,384 | 27.3% |
| 2024 | 2,040 | 26.9% |
| 2025 | 1,796 | 27.0% |
What to check before buying a Mazda B Series
- Lighting & signalling (19.0% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Body, structure & corrosion (13.9% of tests): The one to take seriously on older cars — corrosion to structural areas can be costly and is an MOT failure. Typical repair: £200–£1,500+.
- Brakes (11.2% 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
What is the MOT pass rate for the Mazda B Series?
72.4% of the 12,201 Mazda B Series MOT tests in this dataset passed, a 27.6% fail rate, across model years 1981–2020.
What does the Mazda B Series most often fail its MOT on?
Lighting & signalling, recorded in 19.0% of tests, then body, structure & corrosion (13.9%).
How much does mileage affect B Series MOT results?
Fail rates run at 15.4% for cars in the 0-30k band and 29.0% for 150k+, a 13.6-point difference.
Methodology & source. Based on 12,201 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.