Mercedes-Benz A-Class: what fails at MOT
603,000 MOT tests on the Mercedes-Benz A-Class in 2024, counted. 18.3% failed at the first attempt.
The short answer
18.3% of Mercedes-Benz A-Class tests failed at the first attempt. Cars of the same ages averaged 20.2%, so the A-Class is about average for its age.
It fails most often on tyres (4% of tests), lights and electrics (3.1% of tests) and suspension (2.6% 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 | 52,790 | 8.5% | 10.9% | 24,500 17,400 to 33,800 |
| 2020 | 63,928 | 9.3% | 11.5% | 30,700 22,100 to 41,600 |
| 2019 | 91,818 | 11.9% | 13.4% | 38,100 28,200 to 50,300 |
| 2018 | 72,465 | 14.2% | 15.6% | 45,700 34,800 to 58,700 |
| 2017 | 70,966 | 17.3% | 18.2% | 55,400 42,700 to 70,300 |
| 2016 | 66,770 | 19.3% | 21.3% | 65,200 50,800 to 81,600 |
| 2015 | 47,549 | 22.9% | 24.4% | 73,800 58,100 to 92,600 |
| 2014 | 43,199 | 24.8% | 27.7% | 83,300 65,800 to 103,100 |
| 2013 | 30,265 | 24.9% | 30.6% | 88,700 68,000 to 111,800 |
| 2012 | 7,595 | 31.1% | 33.4% | 69,400 50,000 to 93,200 |
| 2011 | 7,274 | 34.2% | 36.1% | 69,200 50,600 to 90,700 |
| 2010 | 8,484 | 36.4% | 38.6% | 74,700 53,300 to 98,100 |
| 2009 | 9,312 | 38.9% | 39.8% | 80,600 59,700 to 103,000 |
| 2008 | 9,152 | 41.1% | 41.5% | 85,800 64,700 to 108,700 |
| 2007 | 8,475 | 40.9% | 41.5% | 88,100 65,900 to 110,600 |
| 2006 | 6,442 | 43.0% | 42.4% | 88,700 67,800 to 112,100 |
| 2005 | 4,234 | 42.9% | 42.2% | 84,800 64,000 to 106,300 |
| 2004 | 1,798 | 44.8% | 42.3% | 80,100 61,300 to 102,400 |
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 A-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 | A-Class | Cars its age |
|---|---|---|
| Tyres | 4.0% | 3.8% |
| Lights and electrics Less than most | 3.1% | 4.6% |
| Suspension | 2.6% | 3.4% |
| Brakes | 2.3% | 3.0% |
| Wipers, washers and windscreen | 2.0% | 2.4% |
| Exhaust and emissions | 1.2% | 1.3% |
| Seat belts and airbags | 0.9% | 0.4% |
| Body and structure | 0.6% | 1.2% |
The parts that fail most
- Wheel2.8%
- Tyre tread1.4%
- Washers1.4%
- Headlamp aim1.3%
- Brake pads1.2%
- Coil spring1.1%
- Engine warning light1.0%
- Airbag warning light0.8%
- Headlamp0.7%
- Wipers0.6%
Share of tests with a failure on that part.
The most common failures
- Tyre tread: below requirements of 1.6mm1.4%
- Coil spring: fractured or broken1.1%
- Brake pads: less than 1.5 mm thick1.0%
- Engine warning light: inoperative or indicates a malfunction1.0%
- Tyre: has a cut in excess of the requirements deep enough to reach the ply or cords1.0%
- Washers: provides insufficient washer liquid0.9%
- Tyre: has ply or cords exposed0.8%
- Airbag warning light: warning lamp indicates a fault0.8%
- Wipers: does not clear the windscreen effectively0.6%
- Linkage ball joint dust cover: ball joint dust cover no longer prevents the ingress of dirt0.5%
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 edge10.7%
- Tyre: slightly damaged/cracking or perishing5.1%
- Brake pads: wearing thin4.7%
- Brake discs: worn, pitted or scored, but not seriously weakened3.9%
- Brake discs: worn, but not excessively2.0%
- Brake pipes: corroded, covered in grease or other material1.9%
- Tyre: has a cut but not deep enough to reach the ply or cords1.1%
- Child Seat fitted not allowing full inspection of adult belt1.0%
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?”
- “Do all the lights work, including the number plate lights and brake lights?”
- “Have any suspension parts been replaced, such as springs, ball joints or bushes, and can I see the invoice?”
- “When were the brake pads and discs last changed?”
Check a Mercedes-Benz A-Class's own MOT record
Looking at a A-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.