Mercedes-Benz C-Class MOT failure rate and common faults
343,026 Mercedes-Benz C-Class cars aged 3 to 20 took their MOT in 2025, and 24.8% failed at the first attempt. An average car of the same age failed 29.1% of the time, which makes the Mercedes-Benz C-Class 15% less likely to fail than the typical car on the road. Here is what fails, and which years to look for.
24.8%
failed first time
343,026 MOT tests in 2025
-15%
vs same age average
average car of this age mix: 29.1%
69 of 208
age adjusted rank
among cars; 1 fails least
122.0
dangerous defects per 1,000
same age average: 107.5
What fails on a Mercedes-Benz C-Class MOT
Failure items recorded per 1,000 tests, by part of the car, set against an average car with exactly the same spread of ages. A figure well above average is a weak spot worth checking before you buy.
The most common Mercedes-Benz C-Class MOT failures
The individual failure items testers recorded most often, per 1,000 tests.
| Failure item | Area | Per 1,000 tests |
|---|---|---|
| Ball joint excessively worn | Suspension | 52.9 |
| Tread depth below requirements of 1.6mm | Tyres | 43.5 |
| Coil spring: fractured or broken | Suspension | 29.2 |
| Malfunction indicator lamp: inoperative or indicates a malfunction | Engine, emissions and leaks | 27.0 |
| Tyres: has ply or cords exposed | Tyres | 20.9 |
| Tyres: has a cut in excess of the requirements deep enough to reach the ply or cords | Tyres | 18.0 |
| Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt | Suspension | 17.2 |
| Rigid brake pipes: excessively corroded | Brakes | 16.2 |
| Ball joint dust cover no longer prevents the ingress of dirt | Suspension | 14.8 |
| Brake pads: less than 1.5 mm thick | Brakes | 14.4 |
Mercedes-Benz C-Class MOT failure rate by year
Every car fails more often as it ages, so each registration year is compared with the average for all cars of the same age. Years with fewer than 500 tests are left out.
| First registered | Tests | Failed | Same age average | Average mileage |
|---|---|---|---|---|
| 2022 | 4,671 | 10.9% | 11.4% | 28,900 |
| 2021 | 6,195 | 12.8% | 12.8% | 39,000 |
| 2020 | 9,956 | 14.2% | 14.1% | 44,400 |
| 2019 | 24,651 | 14.4% | 16.5% | 49,500 |
| 2018 | 28,371 | 16.1% | 19.1% | 59,700 |
| 2017 | 39,537 | 18.4% | 21.8% | 69,200 |
| 2016 | 36,607 | 19.6% | 25.1% | 82,300 |
| 2015 | 34,050 | 22.0% | 28.1% | 92,800 |
| 2014 | 25,195 | 24.8% | 31.4% | 96,200 |
| 2013 | 23,428 | 30.2% | 34.3% | 102,200 |
| 2012 | 25,670 | 32.6% | 36.6% | 106,900 |
| 2011 | 18,782 | 32.5% | 38.8% | 112,200 |
| 2010 | 12,767 | 34.0% | 40.7% | 112,400 |
| 2009 | 12,609 | 35.6% | 41.8% | 120,000 |
| 2008 | 13,130 | 36.3% | 42.9% | 122,000 |
| 2007 | 11,390 | 38.3% | 42.7% | 119,600 |
| 2006 | 8,750 | 41.1% | 43.0% | 117,700 |
| 2005 | 7,267 | 40.3% | 42.4% | 119,400 |
Advisories to look for in a Mercedes-Benz C-Class's MOT history
An advisory is a tester's warning that something is wearing but has not failed yet. These are the ones written most often on the Mercedes-Benz C-Class, per 1,000 tests. If the car you are looking at has one of these, ask whether it has been fixed since.
- Tread depth: worn close to legal limit/worn on edge328.0
- Rigid brake pipes: corroded, covered in grease or other material117.4
- Brake discs: worn, pitted or scored, but not seriously weakened111.7
- Brake pads: wearing thin88.2
- Tyres: slightly damaged/cracking or perishing70.9
- Ball joint has slight play69.0
Checking a used Mercedes-Benz C-Class before you buy
Against cars of the same age, the Mercedes-Benz C-Class fails more often than average on tyres and wheels. Start there.
Tyres
Check the tread across the full width of every tyre, inner edge included. Uneven wear points to worn suspension or out of line steering geometry.
Wheels
Look for damaged rims, missing wheel nuts and cracked alloys, particularly on the inside edge where kerb damage hides.
Averages only take you so far. The specific car's MOT history shows whether it has already failed on any of these, how often advisories were ignored, and whether the mileage climbs steadily from test to test. Read our guide to reading a car's MOT history before you go to view it.
Fuel mix of the Mercedes-Benz C-Class cars tested: Diesel 61%, Petrol 31%, Hybrid 6%. Average age at test 10.8 years, average recorded mileage 87,800.
Mercedes-Benz C-Class MOT questions
What is the Mercedes-Benz C-Class MOT failure rate?
24.8% of Mercedes-Benz C-Class cars failed their first MOT test of 2025, from 343,026 tests on vehicles aged 3 to 20. An average car with the same age mix failed 29.1% of the time, so the Mercedes-Benz C-Class was 15% less likely to fail.
What fails most often on a Mercedes-Benz C-Class MOT?
Suspension caused the most failure items, at 151 per 1,000 tests. The single most common failure item was "Ball joint excessively worn", recorded 52.9 times per 1,000 tests.
Which Mercedes-Benz C-Class year has the best MOT record?
Measured against cars of the same age, 2016 registrations did best: 19.6% failed against an average of 25.1% for cars that age. Older cars always fail more often, so compare a year with its age group rather than with newer cars.
Does this tell me whether a particular Mercedes-Benz C-Class will pass?
No. These are averages across every Mercedes-Benz C-Class tested in 2025. The car in front of you has its own record: its full MOT history shows every pass, failure and advisory it has had, and it is free to view by registration.
Other Mercedes-Benz models
- Mercedes-Benz A-Class21.5% failed
- Mercedes-Benz E-Class22.3% failed
- Mercedes-Benz GLA16.8% failed
- Mercedes-Benz GLC13.7% failed
- Mercedes-Benz Vito32.5% failed
- Mercedes-Benz CLA19.4% failed
Ranked close to the Mercedes-Benz C-Class
- Volkswagen T-Crossrank 66
- BMW 1 Seriesrank 67
- Jaguar XErank 68
- Volvo V70rank 70
How these figures are calculated
Source: DVSA Anonymised MOT tests and results, 2025 release. We count first tests of cars and small vans (class 4) aged 3 to 20, so a car that fails and is retested is counted once. A failure includes faults fixed and passed within the same visit. The same age average weights the national failure rate for each age by how many Mercedes-Benz C-Class cars of that age were tested, so a model is never penalised for having an older fleet. Make and model are as recorded at the test; trim levels are combined. Full method and rankings.
Contains public sector information licensed under the Open Government Licence v3.0.