1999 Mercedes-Benz Clk — MOT failures & pass rate
Across 6,206 MOT tests, the 1999 Mercedes-Benz Clk recorded a 77.7% pass rate. That is effectively the same as coupes & convertibles of a similar age (22.1% fail rate), so the MOT record here is unremarkable in either direction. Failures cluster in lighting & signalling, brakes and suspension.
What the MOT record shows
One area stands out: lighting & signalling, recorded in 14.1% of tests against 7.8% for the next-worst category.
At component level the recurring items are headlamp aim, headlamp and catalyst emissions — headlamp aim alone was recorded 448 times.
A 150k+ example is materially riskier than a 0-30k one: 29.7% versus 9.3%.
Brakes is the most common advisory, noted on 38.6% 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 | 14.1% | 873 |
| 2 | Brakes | 7.8% | 484 |
| 3 | Suspension | 7.1% | 441 |
| 4 | Tyres | 4.7% | 294 |
| 5 | Visibility | 4.6% | 284 |
| 6 | Emissions & environmental | 4.6% | 283 |
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 | 448 |
| 2 | Headlamp | 344 |
| 3 | Catalyst emissions | 325 |
| 4 | Rigid brake pipes | 258 |
| 5 | Component mounting prescribed areas | 214 |
| 6 | Side repeaters | 195 |
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 | 38.6% | 2,394 |
| 2 | Suspension | 32.4% | 2,012 |
| 3 | Tyres | 24.6% | 1,528 |
| 4 | Lighting & signalling | 17.4% | 1,081 |
| 5 | Emissions & environmental | 15.3% | 948 |
| 6 | Other defects | 13.4% | 830 |
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 | 108 | 9.3% |
| 30-60k | 598 | 14.5% |
| 60-90k | 1,499 | 17.7% |
| 90-120k | 1,748 | 22.9% |
| 120-150k | 1,362 | 26.3% |
| 150k+ | 851 | 29.7% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,676 | 22.6% |
| 2022 | 1,516 | 22.4% |
| 2023 | 1,222 | 21.9% |
| 2024 | 963 | 22.9% |
| 2025 | 829 | 21.7% |
What to check before buying a 1999 Clk
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 14.1% of tests. Start there.
- Lighting & signalling (14.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (7.8% 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.
- Suspension (7.1% 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.
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 1999 Mercedes-Benz Clks pass their MOT?
77.7% of the 6,206 1999 Mercedes-Benz Clk MOT tests in this dataset passed — a 22.3% fail rate.
What is the most common MOT failure on a 1999 Mercedes-Benz Clk?
Lighting & signalling, recorded in 14.1% of tests, followed by brakes (7.8%).
Does the 1999 Clk get worse with mileage?
Its MOT fail rate rises from 9.3% in the 0-30k band to 29.7% in the 150k+ band.
Methodology & source. Based on 6,206 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.