Seat Mii — reliability by registration year
2012–2021 · 9 registration years · 17,800 first tests
Registration years
First-attempt MOT results for every Mii registration year with at least 500 first tests in 2025. Pass rates rise with newer cars, so read a year against its neighbours rather than against the top of the table. Years without their own report are listed here with the same figures.
| Year | First tests | First-attempt pass | Incl. PRS | Most common failure |
|---|---|---|---|---|
| 2021 | 1,055 | 87.0% | 90.1% | |
| 2019 | 1,269 | 84.0% | 88.6% | |
| 2018 | 1,235 | 82.8% | 87.6% | |
| 2017 | 1,436 | 80.2% | 84.1% | |
| 2016 | 2,154 | 74.0% | 79.6% | Catalyst emissions 14.5% |
| 3.0 pp worse than the years either side What failed 2016 Miis most often: Catalyst emissions (14.5%) · Position lamp (front) (14.1%) · Fuel cap/sealing device (11.6%) | ||||
| 2015 | 2,607 | 73.8% | 80.2% | Position lamp (front) 14.3% |
| 2014 | 2,994 | 75.2% | 80.8% | Catalyst emissions 10.1% |
| 3.2 pp better than the years either side What failed 2014 Miis most often: Catalyst emissions (10.1%) · Service brake performance (rear) (9.1%) · Registration plate lamp(s) (7.9%) | ||||
| 2013 | 3,370 | 70.2% | 77.2% | SRS malfunction indicator lamp 12.8% |
| 2012 | 1,680 | 70.0% | 77.0% | SRS malfunction indicator lamp 17.1% |