Diesel Mercedes-Benz A: MOT pass rate
88.9% of diesel Mercedes-Benz As pass the MOT first time, measured across 29,184 DVSA tests on that fuel type alone. Average mileage at test was 41,940.
Diesel against the other Mercedes-Benz A versions
| Fuel | Pass rate | Tests |
|---|---|---|
| Petrol | 90.4% | 62,295 |
| Diesel | 88.9% | 29,184 |
| All Mercedes-Benz A | 90% | 91,485 |
Why the fuel type changes the number
Diesels carry DPFs, EGR valves and stricter smoke limits, so emissions and exhaust faults account for failures petrol cars never see.
On the Mercedes-Benz A specifically, petrol is the strongest at 90.4%, and this diesel version sits 1.1 points below the 90% model average.
What it means if you are buying one
The diesel Mercedes-Benz A fails more often than the model average, so budget for the items that catch this fuel type and treat a fresh MOT as worth paying for. Buying a damaged one? run it through the analyzer, check the exact car, decode the VIN and check the mileage before you bid.
Mileage is part of the answer
The average diesel Mercedes-Benz A had covered 41,940 miles at test, against 32,240 for the petrol. That is below average for a car this age, worth a mileage-consistency check since an unusually low reading is sometimes clocking rather than luck.
Fuel type and mileage are tangled together: diesels are usually bought by higher-mileage drivers, so some of any gap between fuels is the miles rather than the engine. The per-year figures on the Mercedes-Benz A page separate age from fuel if you want to isolate one.
Most common MOT failures on a diesel Mercedes-Benz A
- An SRS malfunction indicator lamp (MIL) indicates a system malfunction, 1% of tests (2.49x the national rate for this defect)
- Number plate does not conform to the specified requirements, 0.3% of tests (1.88x the national rate for this defect)
- Brake lining or pad worn down to wear indicator, 0.4% of tests (1.8x the national rate for this defect)
- Lamp not securely attached, 0.3% of tests (1.58x the national rate for this defect)
- Tyre tread depth not in accordance with the requirements, 3% of tests
- A tyre seriously damaged, 2.7% of tests
- a brake lining or pad worn below 1.5mm, 2% of tests
- A tyre cords visible or damaged, 1.3% of tests
- Engine MIL illuminated indicating a malfunction, 1.2% of tests
- Wiper blade missing or obviously not clearing the windscreen, 0.7% of tests
From 29,300 DVSA-tracked diesel Mercedes-Benz A tests, 2024, split out from the Mercedes-Benz A's other fuel types. DVSA testers marked 8.28% of these flagged defects as "dangerous", against 5.11% nationally. See which fuel type fails on the most dangerous defects nationally for how that compares across the whole fleet.
Most common MOT advisories on a diesel Mercedes-Benz A
Flagged but doesn't fail the car, a different list from the failures above.
- Brake fluid below minimum mark, 0.2% of tests (3.59x the national rate for this defect)
- Brake fluid significantly below minimum mark, 0.3% of tests (3.28x the national rate for this defect)
- Brake disc or drum significantly and obviously worn, 5.2% of tests (1.64x the national rate for this defect)
- a brake lining or pad worn below 1.5mm, 11.8% of tests (1.26x the national rate for this defect), also fails
- Tyre tread depth not in accordance with the requirements, 28.2% of tests, also fails
- A tyre seriously damaged, 12.5% of tests, also fails
- Brake disc or drum excessively weakened, insecure or fractured, 4.6% of tests
- A suspension pin, bush or joint excessively worn, 2.1% of tests
- Number plate inscription missing or illegible, 0.7% of tests
- A wheel badly distorted or wear between wheel and hub at spigot mounting, 0.5% of tests
From 29,300 DVSA-tracked diesel Mercedes-Benz A tests, 2024.
Other Mercedes-Benz A fuel types
- Petrol Mercedes-Benz A - 90.4%