2001 Mercedes-Benz Sl — MOT failures & pass rate
1,614 MOT tests on the 2001 Mercedes-Benz Sl are in this dataset, and 87.7% of them passed. That is 10.2 percentage points better than coupes & convertibles of a similar age, which fail at 22.5%. Failures cluster in lighting & signalling, suspension and visibility.
What the MOT record shows
No single area dominates — lighting & signalling (6.1%) and suspension (4.5%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are ball joint dust cover, headlamp aim and rigid brake pipes — ball joint dust cover alone was recorded 51 times.
Condition tracks the odometer closely. Failures run at 5.2% in the 0-30k band and 28.8% in the 150k+ band, a 23.6-point spread — more than double.
Brakes is the most common advisory, noted on 20.4% of tests — work that passed today but is likely due soon.
The trend is worsening — 10.2% of tests failed in 2021 against 12.5% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 6.1% | 98 |
| 2 | Suspension | 4.5% | 72 |
| 3 | Visibility | 3.1% | 50 |
| 4 | Brakes | 3.0% | 48 |
| 5 | Tyres | 2.2% | 36 |
| 6 | Emissions & environmental | 1.5% | 24 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Ball joint dust cover | 51 |
| 2 | Headlamp aim | 46 |
| 3 | Rigid brake pipes | 26 |
| 4 | Washers | 22 |
| 5 | Wipers | 21 |
| 6 | Component mounting prescribed areas | 20 |
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 | 20.4% | 329 |
| 2 | Suspension | 19.0% | 306 |
| 3 | Tyres | 15.1% | 243 |
| 4 | Emissions & environmental | 12.1% | 196 |
| 5 | Lighting & signalling | 6.8% | 110 |
| 6 | Other defects | 5.1% | 83 |
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 | 134 | 5.2% |
| 30-60k | 473 | 8.3% |
| 60-90k | 496 | 12.9% |
| 90-120k | 346 | 16.5% |
| 120-150k | 106 | 13.2% |
| 150k+ | 59 | 28.8% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 333 | 10.2% |
| 2022 | 332 | 13.6% |
| 2023 | 328 | 13.1% |
| 2024 | 308 | 12.0% |
| 2025 | 313 | 12.5% |
What to check before buying a 2001 Sl
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 6.1% of tests. Start there.
- Lighting & signalling (6.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (4.5% 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.
- Visibility (3.1% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
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 2001 Mercedes-Benz Sls pass their MOT?
87.7% of the 1,614 2001 Mercedes-Benz Sl MOT tests in this dataset passed — a 12.3% fail rate.
What is the most common MOT failure on a 2001 Mercedes-Benz Sl?
Lighting & signalling, recorded in 6.1% of tests, followed by suspension (4.5%).
Does the 2001 Sl get worse with mileage?
Its MOT fail rate rises from 5.2% in the 0-30k band to 28.8% in the 150k+ band.
Methodology & source. Based on 1,614 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.