2009 Mercedes-Benz Cl 500 — MOT failures & pass rate
The 2009 Mercedes-Benz Cl 500 passed 83.0% of its 879 recorded MOT tests. All cars of a similar age fail 25.4% of the time, so this is 8.4pp better than the group it competes with. Failures cluster in brakes, suspension and tyres.
What the MOT record shows
No single area dominates — brakes (8.0%) and suspension (6.4%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are ball joint, rbt (sp) and tread depth — ball joint alone was recorded 28 times.
Condition tracks the odometer closely. Failures run at 14.3% in the 30-60k band and 25.0% in the 120-150k band, a 10.7-point spread.
Brakes is the most common advisory, noted on 27.5% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Brakes | 8.0% | 70 |
| 2 | Suspension | 6.4% | 56 |
| 3 | Tyres | 5.0% | 44 |
| 4 | Lighting & signalling | 3.9% | 34 |
| 5 | Visibility | 2.2% | 19 |
| 6 | Road wheels | 1.0% | 9 |
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 | 28 |
| 2 | Rbt (sp) | 26 |
| 3 | Tread depth | 24 |
| 4 | Rigid brake pipes | 24 |
| 5 | Shock absorbers | 20 |
| 6 | Pins and bushes | 18 |
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 | 27.5% | 242 |
| 2 | Tyres | 22.9% | 201 |
| 3 | Suspension | 19.0% | 167 |
| 4 | Emissions & environmental | 5.1% | 45 |
| 5 | Visibility | 3.0% | 26 |
| 6 | Other defects | 2.8% | 25 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 30-60k | 175 | 14.3% |
| 60-90k | 335 | 17.3% |
| 90-120k | 237 | 15.6% |
| 120-150k | 88 | 25.0% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 192 | 17.7% |
| 2022 | 184 | 16.9% |
| 2023 | 172 | 15.7% |
| 2024 | 173 | 16.8% |
| 2025 | 158 | 17.7% |
What to check before buying a 2009 Cl 500
The failure pattern for this year is specific enough to inspect against: brakes accounted for 8.0% of tests. Start there.
- Brakes (8.0% 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 (6.4% 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.
- Tyres (5.0% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
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 2009 Mercedes-Benz Cl 500s pass their MOT?
83.0% of the 879 2009 Mercedes-Benz Cl 500 MOT tests in this dataset passed — a 17.0% fail rate.
What is the most common MOT failure on a 2009 Mercedes-Benz Cl 500?
Brakes, recorded in 8.0% of tests, followed by suspension (6.4%).
Does the 2009 Cl 500 get worse with mileage?
Its MOT fail rate rises from 14.3% in the 30-60k band to 25.0% in the 120-150k band.
Methodology & source. Based on 879 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.