2004 Mazda Eunos — MOT failures & pass rate
Across 505 MOT tests analysed for the 2004 Mazda Eunos, the most common recorded failure areas were lighting & signalling, brakes and emissions & environmental. Its pass rate of 74.9% was in line with the average for cars of a similar age (74.2%). Higher-mileage examples failed more often — 26.6% in the 150k+ group versus 16.2% in the 60-90k group.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 14.5% | 73 |
| 2 | Brakes | 10.1% | 51 |
| 3 | Emissions & environmental | 7.9% | 40 |
| 4 | Suspension | 7.9% | 40 |
| 5 | Visibility | 5.0% | 25 |
| 6 | Steering | 3.4% | 17 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Catalyst emissions | 47 |
| 2 | Headlamp | 38 |
| 3 | Headlamp aim | 37 |
| 4 | Service brake performance | 33 |
| 5 | Rear fog lamp | 26 |
| 6 | Prescribed areas | 21 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Suspension | 29.3% | 148 |
| 2 | Brakes | 25.7% | 130 |
| 3 | Emissions & environmental | 23.6% | 119 |
| 4 | Tyres | 13.9% | 70 |
| 5 | Body, structure & corrosion | 12.1% | 61 |
| 6 | Lighting & signalling | 8.3% | 42 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 60-90k | 74 | 16.2% |
| 90-120k | 153 | 23.5% |
| 120-150k | 112 | 30.4% |
| 150k+ | 143 | 26.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 126 | 25.4% |
| 2022 | 117 | 26.5% |
| 2023 | 110 | 22.7% |
| 2024 | 78 | 21.8% |
| 2025 | 74 | 29.7% |
What to check before buying a 2004 Eunos
Before buying a 2004 Mazda Eunos, focus on the areas it most often fails on. Lighting & signalling accounted for 14.5% of tests for this year.
- Lighting & signalling (14.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (10.1% 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.
- Emissions & environmental (7.9% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
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 2004 Mazda Eunoss pass their MOT?
74.9% of the 505 2004 Mazda Eunos MOT tests in this dataset passed — a 25.1% fail rate.
What is the most common MOT failure on a 2004 Mazda Eunos?
Lighting & signalling, recorded in 14.5% of tests, followed by brakes (10.1%).
Does the 2004 Eunos get worse with mileage?
Its MOT fail rate rises from 16.2% in the 60-90k band to 26.6% in the 150k+ band.
Methodology & source. Based on 505 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.