2003 Mg Zr+ — MOT failures & pass rate
Across 3,924 MOT tests analysed for the 2003 Mg Zr+, the most common recorded failure areas were lighting & signalling, body, structure & corrosion and brakes. Its pass rate of 74.7% was in line with the average for cars of a similar age (74.3%). Higher-mileage examples failed more often — 32.5% in the 150k+ group versus 16.8% in the 0-30k group.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 14.3% | 560 |
| 2 | Body, structure & corrosion | 10.2% | 399 |
| 3 | Brakes | 9.6% | 377 |
| 4 | Suspension | 6.6% | 258 |
| 5 | Emissions & environmental | 5.9% | 230 |
| 6 | Visibility | 4.7% | 185 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Joints | 257 |
| 2 | Headlamp aim | 245 |
| 3 | Component mounting prescribed areas | 228 |
| 4 | Service brake performance | 213 |
| 5 | Catalyst emissions | 200 |
| 6 | Wipers | 151 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 24.9% | 976 |
| 2 | Tyres | 24.5% | 963 |
| 3 | Body, structure & corrosion | 20.2% | 793 |
| 4 | Suspension | 18.4% | 721 |
| 5 | Emissions & environmental | 13.2% | 519 |
| 6 | Lighting & signalling | 11.6% | 454 |
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 | 191 | 16.8% |
| 30-60k | 844 | 21.0% |
| 60-90k | 1,248 | 26.0% |
| 90-120k | 1,010 | 26.1% |
| 120-150k | 421 | 30.4% |
| 150k+ | 206 | 32.5% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 3,513 | 25.2% |
| Diesel | 411 | 26.0% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,085 | 26.8% |
| 2022 | 887 | 25.0% |
| 2023 | 751 | 24.5% |
| 2024 | 637 | 25.1% |
| 2025 | 564 | 24.1% |
What to check before buying a 2003 Zr+
Before buying a 2003 Mg Zr+, focus on the areas it most often fails on. Lighting & signalling accounted for 14.3% of tests for this year.
- Lighting & signalling (14.3% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Body, structure & corrosion (10.2% of tests): The one to take seriously on older cars — corrosion to structural areas can be costly and is an MOT failure. Typical repair: £200–£1,500+.
- Brakes (9.6% 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.
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 2003 Mg Zr+s pass their MOT?
74.7% of the 3,924 2003 Mg Zr+ MOT tests in this dataset passed — a 25.3% fail rate.
What is the most common MOT failure on a 2003 Mg Zr+?
Lighting & signalling, recorded in 14.3% of tests, followed by body, structure & corrosion (10.2%).
Does the 2003 Zr+ get worse with mileage?
Its MOT fail rate rises from 16.8% in the 0-30k band to 32.5% in the 150k+ band.
Methodology & source. Based on 3,924 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.