2011 Mercedes-Benz C-Class — MOT failures & pass rate
The 2011 Mercedes-Benz C-Class passed 78.6% of its 131,800 recorded MOT tests. Against executive cars of a similar age (19.6% fail rate), the 2011 C-Class comes out 1.7pp worse. Failures cluster in suspension, brakes and lighting & signalling.
What the MOT record shows
No single area dominates — suspension (10.6%) and brakes (8.8%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are ball joint, rigid brake pipes and headlamp aim — ball joint alone was recorded 7,879 times.
A 150k+ example is materially riskier than a 0-30k one: 25.7% versus 9.1%.
The petrol cars hold up better: 17.7% fail against 22.6% for diesel, a 4.8-point gap across 131,800 tests.
Brakes is the most common advisory, noted on 34.1% of tests — work that passed today but is likely due soon.
The trend is worsening — 19.5% of tests failed in 2021 against 22.5% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Suspension | 10.6% | 13,923 |
| 2 | Brakes | 8.8% | 11,550 |
| 3 | Lighting & signalling | 6.7% | 8,809 |
| 4 | Tyres | 6.2% | 8,106 |
| 5 | Emissions & environmental | 3.1% | 4,055 |
| 6 | Visibility | 1.6% | 2,149 |
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 | 7,879 |
| 2 | Rigid brake pipes | 7,824 |
| 3 | Headlamp aim | 5,116 |
| 4 | Tread depth | 4,912 |
| 5 | Linkage ball joint dust cover | 3,264 |
| 6 | Rbt (sp) | 3,209 |
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 | 34.1% | 45,003 |
| 2 | Tyres | 26.5% | 34,918 |
| 3 | Suspension | 21.5% | 28,322 |
| 4 | Emissions & environmental | 7.8% | 10,236 |
| 5 | Other defects | 6.5% | 8,594 |
| 6 | Visibility | 4.6% | 6,119 |
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 | 1,496 | 9.1% |
| 30-60k | 13,785 | 14.4% |
| 60-90k | 35,122 | 18.7% |
| 90-120k | 39,991 | 22.6% |
| 120-150k | 25,519 | 24.8% |
| 150k+ | 15,839 | 25.7% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 99,049 | 22.6% |
| Petrol | 32,751 | 17.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 28,393 | 19.5% |
| 2022 | 27,943 | 20.8% |
| 2023 | 26,871 | 21.6% |
| 2024 | 25,302 | 22.7% |
| 2025 | 23,291 | 22.5% |
What to check before buying a 2011 C-Class
The failure pattern for this year is specific enough to inspect against: suspension accounted for 10.6% of tests. Start there.
- Suspension (10.6% 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 (8.8% 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.
- Lighting & signalling (6.7% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£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 2011 Mercedes-Benz C-Classs pass their MOT?
78.6% of the 131,800 2011 Mercedes-Benz C-Class MOT tests in this dataset passed — a 21.3% fail rate.
What is the most common MOT failure on a 2011 Mercedes-Benz C-Class?
Suspension, recorded in 10.6% of tests, followed by brakes (8.8%).
Does the 2011 C-Class get worse with mileage?
Its MOT fail rate rises from 9.1% in the 0-30k band to 25.7% in the 150k+ band.
Methodology & source. Based on 131,800 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.