Mercedes-Benz C-Class: what fails at MOT
596,000 MOT tests on the Mercedes-Benz C-Class in 2024, counted. 21.7% failed at the first attempt.
The short answer
21.7% of Mercedes-Benz C-Class tests failed at the first attempt. Cars of the same ages averaged 26.2%, so the C-Class does better than most cars its age.
It fails most often on suspension (5.6% of tests), tyres (4.4% of tests) and brakes (3.6% of tests).
By year of registration
Older cars fail more, whatever the model. So each year is shown beside the figure for all cars first used that year.
| First used | Tests | Failed first time | All cars that year | Typical mileage |
|---|---|---|---|---|
| 2021 | 10,639 | 10.9% | 10.9% | 25,600 17,800 to 35,600 |
| 2020 | 18,482 | 10.4% | 11.5% | 32,900 22,800 to 45,800 |
| 2019 | 45,682 | 10.9% | 13.4% | 38,000 27,700 to 50,200 |
| 2018 | 51,468 | 12.6% | 15.6% | 47,000 34,700 to 62,300 |
| 2017 | 71,856 | 14.5% | 18.2% | 57,000 42,100 to 74,200 |
| 2016 | 65,343 | 16.1% | 21.3% | 68,300 51,400 to 89,000 |
| 2015 | 58,728 | 18.6% | 24.4% | 79,700 60,300 to 103,200 |
| 2014 | 43,846 | 20.6% | 27.7% | 85,700 65,300 to 109,400 |
| 2013 | 39,597 | 26.8% | 30.6% | 91,900 70,100 to 118,400 |
| 2012 | 43,611 | 28.8% | 33.4% | 98,400 75,400 to 124,200 |
| 2011 | 31,073 | 29.2% | 36.1% | 106,300 82,400 to 132,400 |
| 2010 | 20,794 | 31.7% | 38.6% | 107,200 81,800 to 134,000 |
| 2009 | 20,181 | 33.0% | 39.8% | 115,900 89,800 to 143,900 |
| 2008 | 21,371 | 34.1% | 41.5% | 118,300 90,700 to 148,000 |
| 2007 | 17,821 | 37.2% | 41.5% | 114,700 87,400 to 144,100 |
| 2006 | 13,967 | 40.7% | 42.4% | 114,000 88,200 to 143,200 |
| 2005 | 12,314 | 41.7% | 42.2% | 118,200 89,800 to 148,300 |
| 2004 | 9,166 | 42.2% | 42.3% | 113,400 86,000 to 142,600 |
Green is at least three points better than other cars that year, red at least three points worse. Typical mileage is the middle reading at the test, with the range the middle half of cars fell in.
Where it fails
The share of Mercedes-Benz C-Class tests with at least one failure in each part of the MOT, beside what cars of the same ages average.
| Part of the test | C-Class | Cars its age |
|---|---|---|
| Suspension | 5.6% | 5.7% |
| Tyres | 4.4% | 4.2% |
| Brakes | 3.6% | 4.3% |
| Lights and electrics Less than most | 3.3% | 7.0% |
| Exhaust and emissions | 2.0% | 2.0% |
| Wipers, washers and windscreen Less than most | 1.4% | 2.9% |
| Body and structure Less than most | 0.5% | 2.1% |
| Seat belts and airbags | 0.5% | 0.6% |
The parts that fail most
- Tyre2.9%
- Ball joint2.6%
- Tyre tread2.0%
- Engine warning light1.5%
- Headlamp aim1.5%
- Coil spring1.4%
- Brake test0.9%
- Brake pads0.9%
- Brake pipes0.8%
- Washers0.8%
Share of tests with a failure on that part.
The most common failures
- Ball joint: excessively worn2.5%
- Tyre tread: below requirements of 1.6mm1.9%
- Engine warning light: inoperative or indicates a malfunction1.5%
- Coil spring: fractured or broken1.4%
- Tyre: has ply or cords exposed1.0%
- Tyre: has a cut in excess of the requirements deep enough to reach the ply or cords0.9%
- Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt0.8%
- Brake pipes: excessively corroded0.7%
- Brake test: efficiency below requirements0.7%
- Brake pads: less than 1.5 mm thick0.7%
What testers warn about
Advisories are things that passed this time but are wearing. They are the best guide to next year's bills.
- Tyre tread: worn close to legal limit/worn on edge12.0%
- Brake pipes: corroded, covered in grease or other material4.5%
- Brake discs: worn, pitted or scored, but not seriously weakened4.4%
- Brake pads: wearing thin4.3%
- Ball joint: has slight play2.9%
- Tyre: slightly damaged/cracking or perishing2.8%
- Suspension pins and bushes: pin or bush worn but not resulting in excessive movement2.2%
- Brake discs: worn, but not excessively2.0%
What these figures can't tell you
An MOT is a safety and emissions test. These figures show how often the model fails that test. They say nothing about engines, gearboxes or electronics that break between tests, and how a car has been looked after matters more than its badge. The car you are looking at has its own MOT record, and that is the one to read.
Ask before you travel
- “Have any suspension parts been replaced, such as springs, ball joints or bushes, and can I see the invoice?”
- “How much tread is left on each tyre, and how old are they?”
- “When were the brake pads and discs last changed?”
- “Do all the lights work, including the number plate lights and brake lights?”
Check a Mercedes-Benz C-Class's own MOT record
Looking at a C-Class? Type its registration to see every test that car has had, what it failed on and what it was warned about, free.
Where this comes from
DVSA anonymised MOT tests and results, 2024, published by the Driver and Vehicle Standards Agency. Contains public sector information licensed under the Open Government Licence v3.0. The counting is Hindsight's own.
First-attempt MOT tests of cars first used 2004 to 2021. A test counts as failed if it failed or only passed after a repair during the test. Retests are left out. Built on 13 November 2026.