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Mercedes-Benz A-Class MOT Failure Rate & Common Faults

We analysed 332,435 MOT tests on the Mercedes-Benz A-Class carried out in 2023. 21% failed at the first attempt, which is noticeably below the 29% average across all cars in the same data. Put another way, about 8 in 10 A-Classes passed first time.

Results cover cars first registered from 1999 to 2021. Compared with other cars of the same age, 2011 models did best (69% passed, +5.8 points against the average for 12-year-old cars), while 1999 models fared worst (56%, −6.0 points). Tested cars had covered 54,453 miles on average, against 73,145 across all cars.

The most common reason for failure was tyres, found on 7.0% of tests (roughly in line with the 6.3% seen across all cars). The single most frequent fault was "not working", on 2.5% of tests.

MOT tests analysed
332,435
First-time pass rate
79%
All cars: 71%
Versus all cars
+7.4 points
Average mileage at test
54,453
All cars: 73,145

Checking a particular A-Class?

See its own MOT history, advisories and mileage for free.

A-Class MOT pass rate by year

Older cars fail more often, so each year is compared with all cars of the same age. Bars above the dashed line did better than average for their age.

Mercedes-Benz A-Class MOT pass rate by year of first registration
First registeredTestsPass rateAll cars, same ageDifferenceAvg mileage
20211,38994%91%+2.8 points23,586
202036,49089%88%+1.3 points25,656
201952,14587%86%+0.7 points32,380
201841,36185%84%+1.0 points39,980
201741,03083%82%+0.9 points50,031
201638,37380%79%+1.2 points59,513
201527,03576%75%+0.8 points68,908
201423,92773%72%+1.1 points78,724
201316,09570%68%+2.2 points85,065
20125,51869%66%+3.6 points67,080
20115,71269%63%+5.8 points68,191
20106,59466%60%+5.0 points74,596
20097,44563%59%+4.2 points79,976
20087,36360%57%+2.9 points85,271
20076,87759%57%+2.0 points86,908
20065,37859%56%+3.0 points88,982
20053,70658%56%+1.9 points86,673
20041,62154%56%−2.0 points81,083
20031,68553%57%−3.6 points82,224
20021,24855%58%−2.3 points83,767
200181955%59%−3.5 points87,445
200034657%61%−3.6 points76,235
199922356%62%−6.0 points78,205

Why the Mercedes-Benz A-Class fails its MOT

The share of tests with at least one failure in each area, compared with all cars.

Most common MOT failure areas for the Mercedes-Benz A-Class
Failure areaA-ClassAll cars
Tyres7.0%6.3%
Lights and electrics5.8%11.3%
Suspension4.3%8.9%
Brakes4.1%6.8%
Visibility3.9%4.8%
Noise, emissions and leaks2.0%3.1%
Seatbelts and airbags1.8%1.0%
Body and structure1.2%3.5%
Road Wheels0.5%0.4%
Number plates and VIN0.4%0.4%

Top 10 specific failure reasons

  1. 1not working2.5%
  2. 2tread depth below requirements of 1.6mm2.3%
  3. 3fractured or broken2.1%
  4. 4provides insufficient washer liquid1.8%
  5. 5less than 1.5 mm thick1.7%
  6. 6has a cut in excess of the requirements deep enough to reach the ply or cords1.7%
  7. 7inoperative or indicates a malfunction1.7%
  8. 8warning lamp indicates a fault1.5%
  9. 9has ply or cords exposed1.3%
  10. 10does not clear the windscreen effectively1.1%

Common A-Class MOT advisories

Advisories don't cause a fail, but they show what's wearing out. On a used A-Class, check whether these have been dealt with. Read our guide to MOT advisories.

Most common MOT advisories for the Mercedes-Benz A-Class
AdvisoryAreaShare of tests
tread depth below requirements of 1.6mmTyres15.8%
has a tear, caused by separation or partial failure of its structureTyres8.3%
less than 1.5 mm thickBrakes8.1%
in such a condition that it is seriously weakenedBrakes6.3%
excessively corrodedBrakes3.9%
significantly and obviously wornBrakes3.0%
tread pattern not visible over the whole tread area when minimum depth required is 1.0mmTyres2.6%
has a cut in excess of the requirements deep enough to reach the ply or cordsTyres1.8%
Child Seat fitted not allowing full inspection of adult beltNon-component advisories1.8%
Nail in tyreNon-component advisories1.8%

Tips to help your A-Class pass

Based on where A-Classes most often fail. For a full list, use our pre-MOT checklist.

  • Lights and electrics · 5.8% of A-Class tests

    Walk round every light

    With a helper, check headlights on dipped and main beam, sidelights, brake lights, indicators, the rear fog light and the number plate lamp. Replace blown bulbs in pairs and make sure no lenses are cracked.

  • Brakes · 4.1% of A-Class tests

    Don't ignore brake warning signs

    Grinding, squealing, a soft pedal or the car pulling to one side under braking are all worth investigating before the MOT. Check whether the last test noted worn pads or discs; if so, they may now be below the limit.

Is the A-Class ULEZ compliant? See the Mercedes-Benz A-Class ULEZ check, or view all Mercedes-Benz models.

Other Mercedes-Benz models

Models with similar pass rates

About this data

Based on 332,435 first MOT tests of the Mercedes-Benz A-Class carried out in 2023.

Source: DVSA anonymised MOT test data (contains public sector information licensed under the Open Government Licence v3.0). First attempts on cars only; “pass rate” means passing first time. Averages cover all 32,735,164 cars tested (71% passed), and years with under 50 tests are hidden.

Learn more about how our data works.

Frequently asked questions

Answers from 332,435 first MOT tests of the Mercedes-Benz A-Class.

What is the Mercedes-Benz A-Class MOT failure rate?

In our data, 21% of 332,435 first MOT attempts on the Mercedes-Benz A-Class ended in a fail, compared with 29% for all cars.

What is the most common reason a Mercedes-Benz A-Class fails its MOT?

The most common failure areas were tyres (7.0% of tests), lights and electrics (5.8% of tests), suspension (4.3% of tests).

Which A-Class year has the best MOT pass rate?

Allowing for age, 2011 cars performed best: 69% passed first time, +5.8 points against the average for 12-year-old cars. The weakest was 1999, at 56% (−6.0 points).

How many miles had a typical Mercedes-Benz A-Class covered at its MOT?

The average was 54,453 miles, against 73,145 for all cars tested. 2021 cars averaged 23,586 miles and 1999 cars 78,205.

What is the most common MOT advisory on the Mercedes-Benz A-Class?

"tread depth below requirements of 1.6mm" was recorded on 15.8% of tests, in the tyres area. 7.0% of A-Classes failed in that area too.

How can I check a specific A-Class's MOT history?

Enter its registration in our free MOT check. Across the 332,435 A-Classes in our data, first-time pass rates ranged from 53% to 94% by year, so one car's own record says more than the average.

Check any A-Class's MOT history

Every test, failure, advisory and recorded mileage for a specific car. Free, from official DVSA data.