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BMW 420 MOT reliability
BMW 420s passed their MOT first time 82% of the time across 61,591 tests in 2025.
First-time pass rate
82%
MOTs analysed
61,591
Still licensed (GB)
–
Body type
–
Pass rate by year of first registration
In detail:
First registered
2020
2020 petrol
2,145 MOTs
Passed first time 87%. Typical mileage 36,938 (most between 28,190 and 47,398).
2021: 100% → 2022: 95% → 2023: 89% → 2024: 88% → 2025: 87%
Most common failures
- Condition: has a cut in excess of the requirements deep enough to reach the ply or cords (2.6%)
- Condition: has ply or cords exposed (2.1%)
- Brake pads: less than 1.5 mm thick (1.3%)
- Tread depth below requirements of 1.6mm (1.3%)
- Washers: provides insufficient washer liquid (1.3%)
2020 diesel
916 MOTs
Passed first time 85%. Typical mileage 43,732 (most between 31,878 and 56,544).
2021: 100% → 2022: 87% → 2023: 89% → 2024: 86% → 2025: 85%
Most common failures
- Condition: has ply or cords exposed (3.1%)
- Condition: has a cut in excess of the requirements deep enough to reach the ply or cords (2.5%)
- Tread depth below requirements of 1.6mm (1.7%)
- Brake pads: less than 1.5 mm thick (1.6%)
- Malfunction indicator lamp: inoperative or indicates a malfunction (1.5%)
Where 2020 420s fail
Wheels & tyres
7.1%
Lights & electrics
2.1%
Visibility & wipers
2.0%
Brakes
1.8%
Suspension & axles
0.6%
Exhaust, emissions & leaks
0.2%
Body, structure & corrosion
0.1%
Steering
0.0%
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