2017 MG MG3 — MOT failures & pass rate
Across 16,857 MOT tests, the 2017 MG MG3 recorded an 83.9% pass rate. Superminis of a similar age fail 13.4% of the time, so this is 2.7pp worse than the group it competes with. Failures cluster in tyres, brakes and lighting & signalling.
What the MOT record shows
No single area dominates — tyres (6.8%) and brakes (6.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, wipers and tread depth — headlamp aim alone was recorded 578 times.
A 90-120k example is materially riskier than a 0-30k one: 30.1% versus 10.1%.
Advisories point at the next bill rather than this one: tyres was flagged on 27.2% of tests without failing them.
The trend is worsening — 11.1% of tests failed in 2021 against 20.2% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 6.8% | 1,141 |
| 2 | Brakes | 6.1% | 1,035 |
| 3 | Lighting & signalling | 4.8% | 812 |
| 4 | Visibility | 4.5% | 763 |
| 5 | Suspension | 3.5% | 582 |
| 6 | Seat belts & restraints | 1.4% | 241 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Headlamp aim | 578 |
| 2 | Wipers | 513 |
| 3 | Tread depth | 444 |
| 4 | Washers | 402 |
| 5 | Rbt (sp) | 389 |
| 6 | Coil spring | 293 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 27.2% | 4,584 |
| 2 | Brakes | 20.8% | 3,499 |
| 3 | Suspension | 14.6% | 2,458 |
| 4 | Other defects | 8.9% | 1,494 |
| 5 | Visibility | 3.3% | 561 |
| 6 | Emissions & environmental | 1.8% | 305 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 6,917 | 10.1% |
| 30-60k | 7,736 | 18.6% |
| 60-90k | 1,910 | 25.2% |
| 90-120k | 259 | 30.1% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 3,220 | 11.1% |
| 2022 | 3,314 | 13.5% |
| 2023 | 3,410 | 16.2% |
| 2024 | 3,454 | 19.0% |
| 2025 | 3,459 | 20.2% |
What to check before buying a 2017 MG3
On a 2017 MG3, tyres is what the MOT record says goes wrong most — it appeared in 6.8% of tests. Check these areas before you commit.
- Tyres (6.8% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
- Brakes (6.1% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Lighting & signalling (4.8% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2017 MG MG3s pass their MOT?
83.9% of the 16,857 2017 MG MG3 MOT tests in this dataset passed — a 16.1% fail rate.
What is the most common MOT failure on a 2017 MG MG3?
Tyres, recorded in 6.8% of tests, followed by brakes (6.1%).
Does the 2017 MG3 get worse with mileage?
Its MOT fail rate rises from 10.1% in the 0-30k band to 30.1% in the 90-120k band.
Methodology & source. Based on 16,857 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.