SEAT Mii MOT Failure Rate & Common Faults
We analysed 17,713 MOT tests on the SEAT Mii carried out in 2023. 21% failed at the first attempt, which is noticeably below the 29% average across all cars in the same data. Put another way, about 8 in 10 Miis passed first time.
Results cover cars first registered from 2012 to 2020. Compared with other cars of the same age, 2014 models did best (79% passed, +6.9 points against the average for 9-year-old cars), while 2020 models fared worst (85%, −2.4 points). Tested cars had covered 45,856 miles on average, against 73,145 across all cars.
The most common reason for failure was lights and electrics, found on 7.1% of tests (noticeably below the 11.3% seen across all cars). The single most frequent fault was "not working", on 2.5% of tests.
- MOT tests analysed
- 17,713
- First-time pass rate
- 79%
- All cars: 71%
- Versus all cars
- +7.6 points
- Average mileage at test
- 45,856
- All cars: 73,145
Checking a particular Mii?
See its own MOT history, advisories and mileage for free.
Mii MOT pass rate by year
Older cars fail more often, so each year is compared with all cars of the same age. Bars above the dashed line did better than average for their age.
| First registered | Tests | Pass rate | All cars, same age | Difference | Avg mileage |
|---|---|---|---|---|---|
| 2020 | 278 | 85% | 88% | −2.4 points | 14,122 |
| 2019 | 1,321 | 90% | 86% | +3.5 points | 20,744 |
| 2018 | 1,261 | 85% | 84% | +0.8 points | 26,930 |
| 2017 | 1,477 | 85% | 82% | +3.2 points | 33,098 |
| 2016 | 2,227 | 79% | 79% | +0.3 points | 39,780 |
| 2015 | 2,697 | 79% | 75% | +3.8 points | 45,983 |
| 2014 | 3,107 | 79% | 72% | +6.9 points | 52,224 |
| 2013 | 3,542 | 74% | 68% | +5.6 points | 58,858 |
| 2012 | 1,781 | 72% | 66% | +6.0 points | 64,249 |
Why the SEAT Mii fails its MOT
The share of tests with at least one failure in each area, compared with all cars.
| Failure area | Mii | All cars |
|---|---|---|
| Lights and electrics | 7.1% | 11.3% |
| Brakes | 5.6% | 6.8% |
| Visibility | 4.2% | 4.8% |
| Tyres | 4.0% | 6.3% |
| Body and structure | 2.3% | 3.5% |
| Suspension | 2.2% | 8.9% |
| Seatbelts and airbags | 2.0% | 1.0% |
| Noise, emissions and leaks | 1.7% | 3.1% |
| Steering | 0.2% | 1.8% |
| Road Wheels | 0.1% | 0.4% |
Top 10 specific failure reasons
- 1not working2.5%
- 2excessively binding2.4%
- 3does not clear the windscreen effectively2.3%
- 4tread depth below requirements of 1.6mm1.7%
- 5warning lamp indicates a fault1.7%
- 6too low1.6%
- 7ineffective1.4%
- 8inoperative in the case of a single lamp or all lamps1.2%
- 9provides insufficient washer liquid1.0%
- 10less than 1.5 mm thick1.0%
Common Mii MOT advisories
Advisories don't cause a fail, but they show what's wearing out. On a used Mii, check whether these have been dealt with. Read our guide to MOT advisories.
| Advisory | Area | Share of tests |
|---|---|---|
| has a tear, caused by separation or partial failure of its structure | Tyres | 13.0% |
| tread depth below requirements of 1.6mm | Tyres | 11.6% |
| in such a condition that it is seriously weakened | Brakes | 6.2% |
| less than 1.5 mm thick | Brakes | 4.2% |
| pin or bush excessively worn | Suspension | 3.6% |
| excessively binding | Brakes | 3.3% |
| significantly and obviously worn | Brakes | 2.6% |
| tread pattern not visible over the whole tread area when minimum depth required is 1.0mm | Tyres | 1.6% |
| Play in steering rack inner joint(s) | Non-component advisories | 1.6% |
| Nail in tyre | Non-component advisories | 1.2% |
Tips to help your Mii pass
Based on where Miis most often fail. For a full list, use our pre-MOT checklist.
Lights and electrics · 7.1% of Mii tests
Walk round every light
With a helper, check headlights on dipped and main beam, sidelights, brake lights, indicators, the rear fog light and the number plate lamp. Replace blown bulbs in pairs and make sure no lenses are cracked.
Brakes · 5.6% of Mii tests
Don't ignore brake warning signs
Grinding, squealing, a soft pedal or the car pulling to one side under braking are all worth investigating before the MOT. Check whether the last test noted worn pads or discs; if so, they may now be below the limit.
Visibility · 4.2% of Mii tests
Clear the view
Replace wiper blades that smear, fill the washer bottle and get chips in the windscreen repaired early, especially in the area directly in front of the driver.
Compare with other models
Is the Mii ULEZ compliant? See the SEAT Mii ULEZ check, or view all SEAT models.
Other SEAT models
Models with similar pass rates
About this data
Based on 17,713 first MOT tests of the SEAT Mii carried out in 2023.
Source: DVSA anonymised MOT test data (contains public sector information licensed under the Open Government Licence v3.0). First attempts on cars only; “pass rate” means passing first time. Averages cover all 32,735,164 cars tested (71% passed), and years with under 50 tests are hidden.
Learn more about how our data works.
Frequently asked questions
Answers from 17,713 first MOT tests of the SEAT Mii.
What is the SEAT Mii MOT failure rate?
In our data, 21% of 17,713 first MOT attempts on the SEAT Mii ended in a fail, compared with 29% for all cars.
What is the most common reason a SEAT Mii fails its MOT?
The most common failure areas were lights and electrics (7.1% of tests), brakes (5.6% of tests), visibility (4.2% of tests).
Which Mii year has the best MOT pass rate?
Allowing for age, 2014 cars performed best: 79% passed first time, +6.9 points against the average for 9-year-old cars. The weakest was 2020, at 85% (−2.4 points).
How many miles had a typical SEAT Mii covered at its MOT?
The average was 45,856 miles, against 73,145 for all cars tested. 2020 cars averaged 14,122 miles and 2012 cars 64,249.
What is the most common MOT advisory on the SEAT Mii?
"has a tear, caused by separation or partial failure of its structure" was recorded on 13.0% of tests, in the tyres area. 4.0% of Miis failed in that area too.
How can I check a specific Mii's MOT history?
Enter its registration in our free MOT check. Across the 17,713 Miis in our data, first-time pass rates ranged from 72% to 90% by year, so one car's own record says more than the average.
Related guides
- MOT · 6 min readPre-MOT checklist: 20 things to check yourself before the testTwenty quick checks, grouped by area, that you can do on your driveway in under half an hour. No tools beyond a coin and a helper needed for most.Read the guide
- MOT · 6 min readDangerous, major and minor MOT defects explainedSince 2018, every fault found at an MOT goes into one of four categories. Knowing the difference tells you whether you can drive home, and what to fix first.Read the guide
- MOT · 4 min readTyre tread depth and the MOT: the legal limit and how to check6.3% of cars failed their 2023 MOT on tyres. The 1.6mm legal limit, what testers look for beyond tread, and a one-minute check with a 20p coin.Read the guide
Check any Mii's MOT history
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