2021 Audi A3 30 — MOT failures & pass rate
Across 4,986 MOT tests analysed for the 2021 Audi A3 30, the most common recorded failure areas were tyres, lighting & signalling and visibility. Its pass rate of 92.1% was in line with the average for cars of a similar age (91.2%). Higher-mileage examples failed more often — 17.6% in the 90-120k group versus 6.2% in the 0-30k group.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.1% | 257 |
| 2 | Lighting & signalling | 1.6% | 80 |
| 3 | Visibility | 1.0% | 51 |
| 4 | Brakes | 0.9% | 44 |
| 5 | Suspension | 0.8% | 39 |
| 6 | Seat belts & restraints | 0.6% | 29 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 94 |
| 2 | Headlamp aim | 74 |
| 3 | Brake pads | 39 |
| 4 | Wipers | 27 |
| 5 | Shock absorbers | 25 |
| 6 | Washers | 21 |
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 | 24.6% | 1,227 |
| 2 | Other defects | 8.0% | 401 |
| 3 | Brakes | 7.6% | 379 |
| 4 | Suspension | 6.8% | 340 |
| 5 | Visibility | 3.0% | 148 |
| 6 | Lighting & signalling | 0.2% | 8 |
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 | 2,446 | 6.2% |
| 30-60k | 2,069 | 8.4% |
| 60-90k | 387 | 14.0% |
| 90-120k | 74 | 17.6% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 4,042 | 7.5% |
| Diesel | 943 | 9.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 121 | 5.8% |
| 2024 | 2,438 | 7.3% |
| 2025 | 2,427 | 8.7% |
What to check before buying a 2021 A3 30
Before buying a 2021 Audi A3 30, focus on the areas it most often fails on. Tyres accounted for 5.1% of tests for this year.
- Tyres (5.1% 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.
- Lighting & signalling (1.6% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Visibility (1.0% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£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 2021 Audi A3 30s pass their MOT?
92.1% of the 4,986 2021 Audi A3 30 MOT tests in this dataset passed — a 7.9% fail rate.
What is the most common MOT failure on a 2021 Audi A3 30?
Tyres, recorded in 5.1% of tests, followed by lighting & signalling (1.6%).
Does the 2021 A3 30 get worse with mileage?
Its MOT fail rate rises from 6.2% in the 0-30k band to 17.6% in the 90-120k band.
Methodology & source. Based on 4,986 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.