2006 Smart Forfour — MOT failures & pass rate
Across 3,568 MOT tests, the 2006 Smart Forfour recorded a 72.8% pass rate. That is 1.6 percentage points better than city cars of a similar age, which fail at 28.8%. Failures cluster in lighting & signalling, suspension and brakes.
What the MOT record shows
One area stands out: lighting & signalling, recorded in 19.8% of tests against 10.2% for the next-worst category.
At component level the recurring items are headlamp aim, headlamp and position lamp — headlamp aim alone was recorded 330 times.
A 150k+ example is materially riskier than a 0-30k one: 29.6% versus 12.9%.
The petrol cars hold up better: 26.2% fail against 31.4% for diesel, a 5.2-point gap across 3,568 tests.
Suspension is the most common advisory, noted on 34.2% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 19.8% | 707 |
| 2 | Suspension | 10.2% | 364 |
| 3 | Brakes | 8.9% | 319 |
| 4 | Body, structure & corrosion | 6.5% | 233 |
| 5 | Tyres | 5.6% | 201 |
| 6 | Visibility | 5.2% | 185 |
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 | 330 |
| 2 | Headlamp | 303 |
| 3 | Position lamp | 198 |
| 4 | Track rod end | 166 |
| 5 | Stop lamp | 160 |
| 6 | Wipers | 130 |
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 | 34.2% | 1,220 |
| 2 | Brakes | 26.1% | 930 |
| 3 | Lighting & signalling | 24.9% | 889 |
| 4 | Tyres | 24.9% | 887 |
| 5 | Other defects | 11.9% | 423 |
| 6 | Body, structure & corrosion | 8.5% | 303 |
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 | 62 | 12.9% |
| 30-60k | 397 | 16.4% |
| 60-90k | 1,181 | 26.7% |
| 90-120k | 1,188 | 30.7% |
| 120-150k | 479 | 28.4% |
| 150k+ | 250 | 29.6% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 2,919 | 26.2% |
| Diesel | 649 | 31.4% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 960 | 27.6% |
| 2022 | 816 | 25.7% |
| 2023 | 714 | 27.0% |
| 2024 | 589 | 28.5% |
| 2025 | 489 | 27.2% |
What to check before buying a 2006 Forfour
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 19.8% of tests. Start there.
- Lighting & signalling (19.8% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (10.2% 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.
- Brakes (8.9% 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 many 2006 Smart Forfours pass their MOT?
72.8% of the 3,568 2006 Smart Forfour MOT tests in this dataset passed — a 27.2% fail rate.
What is the most common MOT failure on a 2006 Smart Forfour?
Lighting & signalling, recorded in 19.8% of tests, followed by suspension (10.2%).
Does the 2006 Forfour get worse with mileage?
Its MOT fail rate rises from 12.9% in the 0-30k band to 29.6% in the 150k+ band.
Methodology & source. Based on 3,568 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.