Mercedes-Benz CLA: what fails at MOT
109,000 MOT tests on the Mercedes-Benz CLA in 2024, counted. 16.5% failed at the first attempt.
The short answer
16.5% of Mercedes-Benz CLA tests failed at the first attempt. Cars of the same ages averaged 18.1%, so the CLA is about average for its age.
It fails most often on tyres (4.7% of tests), suspension (1.7% of tests) and lights and electrics (1.7% 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 | 13,525 | 11.6% | 10.9% | 28,600 20,400 to 38,800 |
| 2020 | 11,339 | 11.9% | 11.5% | 34,100 24,400 to 45,900 |
| 2019 | 12,723 | 13.6% | 13.4% | 39,300 29,400 to 51,800 |
| 2018 | 14,973 | 15.0% | 15.6% | 48,700 37,200 to 61,700 |
| 2017 | 15,478 | 17.5% | 18.2% | 60,500 47,500 to 75,700 |
| 2016 | 14,822 | 19.2% | 21.3% | 70,600 55,600 to 87,800 |
| 2015 | 13,295 | 19.5% | 24.4% | 77,900 62,400 to 97,400 |
| 2014 | 8,766 | 21.9% | 27.7% | 85,700 67,600 to 106,400 |
| 2013 | 3,976 | 24.2% | 30.6% | 90,900 71,700 to 109,500 |
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 CLA tests with at least one failure in each part of the MOT, beside what cars of the same ages average.
| Part of the test | CLA | Cars its age | |
|---|---|---|---|
| Tyres | 4.7% | 3.7% | |
| Suspension | 1.7% | 2.7% | Less than most |
| Lights and electrics | 1.7% | 3.7% | Less than most |
| Brakes | 1.6% | 2.5% | Less than most |
| Wipers, washers and windscreen | 1.6% | 2.2% | |
| Exhaust and emissions | 1.1% | 1.0% | |
| Seat belts and airbags | 0.6% | 0.3% | |
| Wheels | 0.4% | 0.2% |
The parts that fail most
- Tyre3.6%
- Tyre tread1.4%
- Brake pads1.1%
- Engine warning light1.0%
- Washers1.0%
- Coil spring0.8%
- Headlamp aim0.8%
- Wipers0.6%
- Airbag warning light0.5%
- Linkage ball joint dust cover0.4%
Share of tests with a failure on that part.
The most common failures
- Tyre: has ply or cords exposed1.3%
- Tyre tread: below requirements of 1.6mm1.3%
- Tyre: has a cut in excess of the requirements deep enough to reach the ply or cords1.2%
- Engine warning light: inoperative or indicates a malfunction1.0%
- Brake pads: less than 1.5 mm thick0.9%
- Coil spring: fractured or broken0.8%
- Washers: provides insufficient washer liquid0.7%
- Tyre: has a bulge, caused by separation or partial failure of its structure0.5%
- Wipers: does not clear the windscreen effectively0.5%
- Airbag warning light: warning lamp indicates a fault0.5%
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 edge10.0%
- Brake pads: wearing thin4.3%
- Tyre: slightly damaged/cracking or perishing3.9%
- Brake discs: worn, pitted or scored, but not seriously weakened3.7%
- Brake discs: worn, but not excessively1.8%
- Tyre: has a cut but not deep enough to reach the ply or cords1.3%
- Child Seat fitted not allowing full inspection of adult belt1.1%
- Nail in tyre1.0%
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
- “How much tread is left on each tyre, and how old are they?”
- “Have any suspension parts been replaced, such as springs, ball joints or bushes, and can I see the invoice?”
- “Do all the lights work, including the number plate lights and brake lights?”
- “When were the brake pads and discs last changed?”
Check a Mercedes-Benz CLA's own MOT record
Type the registration from the advert. You'll 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.