Mercedes-Benz 500 MOT pass rate and common failures

In 2025, 82.3% of Mercedes-Benz 500 MOT tests were a first-time pass, across 910 tests in Great Britain. For all cars it was 71.5%.

Compared with cars of the same age

Older cars fail more often, so a model that’s mostly a few years old will look better than one that’s mostly 12. These figures compare like with like.

At 3–5 years

–

Too few tests at this age to say.

At 6–10 years

–

Too few tests at this age to say.

At 11 years and over

82.3%

All cars: 61.3% (21 points better). 895 tests.

Figures by age, with typical mileage
Age (years)TestsFirst-time passAll carsTypical mileage
20+89582.3%61.4%98,750 miles

Typical mileage is the median reading at the test, to the nearest 2,500 miles.

What fails most often

The share of Mercedes-Benz 500 MOT tests that failed on at least one item in each area, against all cars. A test can fail on several areas at once.

Area500All cars
Lamps, reflectors and electrical equipment13.3%16.6%
Brakes8.1%10.2%
Suspension7.6%13.7%
Noise, emissions and leaks4.0%4.0%
Visibility3.6%5.2%
Body, chassis, structure3.1%4.2%
Steering2.0%2.5%
Tyres1.3%8.4%

Most common reasons for failing

  1. Ball joint dust cover no longer prevents the ingress of dirt failed 3.5% of tests · what this means
  2. Position lamp: not working failed 2.5% of tests · what this means
  3. Service brake performance: excessively binding failed 2.4% of tests · what this means
  4. Non catalyst emissions: emissions carbon monoxide content excessive failed 1.6% of tests · what this means
  5. Rear fog lamp: not working failed 1.4% of tests · what this means
  6. Stop lamp: not working failed 1.3% of tests · what this means
  7. Wipers: does not clear the windscreen effectively failed 1.2% of tests · what this means
  8. Headlamp aim: too low failed 1.1% of tests · what this means
  9. Headlamp aim: too high failed 1.1% of tests · what this means
  10. Washers: provides insufficient washer liquid failed 1.0% of tests · what this means

Checking a particular 500?

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About these figures

Download these figures (CSV) · Other Mercedes-Benz models · All makes

Source: DVSA anonymised MOT test data for 2025. Contains public sector information licensed under the Open Government Licence v3.0. Our own analysis; not produced or endorsed by DVSA.