2014 Mercedes-Benz CLS — MOT failures & pass rate
10,909 MOT tests on the 2014 Mercedes-Benz CLS are in this dataset, and 82.0% of them passed. That is 2.5 percentage points worse than executive cars of a similar age, which fail at 15.5%. Failures cluster in tyres, suspension and brakes.
What the MOT record shows
No single area dominates — tyres (8.9%) and suspension (6.0%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are coil spring, rigid brake pipes and tread depth — coil spring alone was recorded 576 times.
Mileage is the strongest signal on the record: 9.3% of 0-30k cars fail, rising to 19.9% once past 150k — 2.1× the risk.
Split by fuel, diesel examples fail 3.5pp more often than petrol ones (18.1% vs 14.6%) — worth weighing if you have a choice.
Advisories point at the next bill rather than this one: brakes was flagged on 30.3% of tests without failing them.
The trend is worsening — 15.8% of tests failed in 2021 against 19.5% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 8.9% | 971 |
| 2 | Suspension | 6.0% | 659 |
| 3 | Brakes | 4.7% | 516 |
| 4 | Lighting & signalling | 2.4% | 266 |
| 5 | Emissions & environmental | 1.4% | 148 |
| 6 | Road wheels | 1.1% | 124 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Coil spring | 576 |
| 2 | Rigid brake pipes | 470 |
| 3 | Tread depth | 373 |
| 4 | Headlamp aim | 191 |
| 5 | Linkage ball joint dust cover | 127 |
| 6 | Brake pads | 117 |
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 | 30.3% | 3,309 |
| 2 | Tyres | 24.1% | 2,628 |
| 3 | Suspension | 9.9% | 1,079 |
| 4 | Other defects | 4.5% | 488 |
| 5 | Visibility | 3.2% | 350 |
| 6 | Road wheels | 2.0% | 216 |
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 | 321 | 9.3% |
| 30-60k | 2,807 | 15.6% |
| 60-90k | 4,187 | 18.7% |
| 90-120k | 2,351 | 19.4% |
| 120-150k | 895 | 20.1% |
| 150k+ | 347 | 19.9% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 10,376 | 18.1% |
| Petrol | 533 | 14.6% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 2,201 | 15.8% |
| 2022 | 2,238 | 18.1% |
| 2023 | 2,229 | 18.0% |
| 2024 | 2,146 | 18.6% |
| 2025 | 2,095 | 19.5% |
What to check before buying a 2014 CLS
On a 2014 CLS, tyres is what the MOT record says goes wrong most — it appeared in 8.9% of tests. Check these areas before you commit.
- Tyres (8.9% 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.
- Suspension (6.0% 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 (4.7% 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 2014 Mercedes-Benz CLSs pass their MOT?
82.0% of the 10,909 2014 Mercedes-Benz CLS MOT tests in this dataset passed — a 18.0% fail rate.
What is the most common MOT failure on a 2014 Mercedes-Benz CLS?
Tyres, recorded in 8.9% of tests, followed by suspension (6.0%).
Does the 2014 CLS get worse with mileage?
Its MOT fail rate rises from 9.3% in the 0-30k band to 19.9% in the 150k+ band.
Methodology & source. Based on 10,909 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.