Mercedes-Benz R-Class MOT pass rate and common failures
In 2025, 72.2% of Mercedes-Benz R-Class MOT tests were a first-time pass, across 1,725 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
72.0%
All cars: 61.3% (10.7 points better). 1,680 tests.
Pass rate by age
Figures by age, with typical mileage
| Age (years) | Tests | First-time pass | All cars | Typical mileage |
|---|---|---|---|---|
| 12 | 221 | 75.1% | 64.4% | 106,250 miles |
| 13 | 309 | 71.5% | 62.1% | 113,750 miles |
| 14 | 256 | 76.2% | 60.2% | 123,750 miles |
| 15 | 148 | 69.6% | 58.6% | 126,250 miles |
| 16 | 170 | 67.1% | 57.5% | 133,750 miles |
| 17 | 238 | 70.6% | 57.2% | 133,750 miles |
| 18 | 243 | 69.5% | 57.0% | 123,750 miles |
| 19 | 95 | 77.9% | 57.2% | 133,750 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 R-Class MOT tests that failed on at least one item in each area, against all cars. A test can fail on several areas at once.
| Area | R-Class | All cars |
|---|---|---|
| Brakes | 18.4% | 10.2% |
| Lamps, reflectors and electrical equipment | 17.1% | 16.6% |
| Body, chassis, structure | 7.1% | 4.2% |
| Tyres | 5.9% | 8.4% |
| Noise, emissions and leaks | 5.6% | 4.0% |
| Suspension | 5.0% | 13.7% |
| Visibility | 2.9% | 5.2% |
| Seat belts and supplementary restraint systems | 1.9% | 1.1% |
Most common reasons for failing
- Joints: constant velocity boot split or insecure, no longer prevents the ingress of dirt failed 5.1% of tests
- Position lamp: not working failed 4.6% of tests · what this means
- Rigid brake pipes: excessively corroded failed 3.7% of tests · what this means
- Rbt (sp): efficiency below requirements failed 3.2% of tests
- Malfunction indicator lamp: inoperative or indicates a malfunction failed 2.5% of tests · what this means
- Condition: has a cut in excess of the requirements deep enough to reach the ply or cords failed 1.7% of tests
- Stop lamp: not working failed 1.6% of tests · what this means
- Tread depth below requirements of 1.6mm failed 1.6% of tests
- Headlamp aim: too low failed 1.6% of tests · what this means
- Decelerometer (sp): efficiency below requirements failed 1.6% of tests
Checking a particular R-Class?
See its own MOT history, mileage record and advisories in plain English. Free, no sign-up.
About these figures
- They cover every R-Class version DVSA records under this name (engines, trims and generations together), on its first MOT test of each visit. A “pass with rectification” (fixed within an hour) counts as a fail, as in DVSA’s own statistics.
- Cars under three years old are left out, because the few tested that young are mostly taxis.
- Fuel mix of the cars tested: diesel 91.5%, petrol 8.3%, liquefied petrolum gas (lpg) 0.2%.
- A pass rate describes the model, not any one car. How a car has been looked after matters more.
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.