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Mercedes-Benz 300 MOT reliability
Mercedes-Benz 300s passed their MOT first time 78% of the time across 2,636 tests in 2025.
First-time pass rate
78%
MOTs analysed
2,636
Still licensed (GB)
–
Body type
Sedan
Pass rate by year of first registration
In detail:
First registered
2019
2019 hybrid
2 MOTs
Passed first time 100%. Typical mileage 139,169 (most between 136,590 and 141,748).
2022: 100% → 2023: 100% → 2024: 100% → 2025: 100%
Most common failures
2019 diesel
1 MOT
Passed first time 100%. Typical mileage 39,069 (most between 39,069 and 39,069).
2021: 100% → 2024: 100% → 2025: 100%
Most common failures
2019 ed
1 MOT
Passed first time 100%. Typical mileage 58,885 (most between 58,885 and 58,885).
2024: 100% → 2025: 100%
Most common failures
2019 petrol
1 MOT
Passed first time 100%. Typical mileage 9,258 (most between 9,258 and 9,258).
2021: 67% → 2022: 100% → 2023: 100% → 2024: 100% → 2025: 100%
Most common failures
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