2003 MG ZT — MOT failures & pass rate
Across 4,143 MOT tests, the 2003 MG ZT recorded a 71.5% pass rate. Large family cars of a similar age fail at 28.1%, so the 2003 ZT sits squarely on the average. Failures cluster in suspension, brakes and lighting & signalling.
What the MOT record shows
No single area dominates — suspension (14.9%) and brakes (13.5%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, rbt (sp) and rigid brake pipes — headlamp aim alone was recorded 363 times.
Mileage is the strongest signal on the record: 11.8% of 0-30k cars fail, rising to 31.1% once past 150k — 2.6× the risk.
Split by fuel, diesel examples fail 3.5pp more often than petrol ones (30.3% vs 26.8%) — worth weighing if you have a choice.
Advisories point at the next bill rather than this one: brakes was flagged on 37.4% of tests without failing them.
The trend is improving — the fail rate fell from 30.9% in 2021 to 27.3% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Suspension | 14.9% | 618 |
| 2 | Brakes | 13.5% | 559 |
| 3 | Lighting & signalling | 13.4% | 554 |
| 4 | Seat belts & restraints | 5.6% | 233 |
| 5 | Body, structure & corrosion | 4.9% | 203 |
| 6 | Tyres | 4.8% | 198 |
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 | 363 |
| 2 | Rbt (sp) | 265 |
| 3 | Rigid brake pipes | 262 |
| 4 | Component mounting prescribed areas | 246 |
| 5 | SRS malfunction indicator lamp | 187 |
| 6 | Headlamp | 177 |
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 | 37.4% | 1,548 |
| 2 | Suspension | 34.8% | 1,444 |
| 3 | Tyres | 23.6% | 978 |
| 4 | Lighting & signalling | 14.0% | 578 |
| 5 | Body, structure & corrosion | 11.4% | 474 |
| 6 | Other defects | 9.6% | 398 |
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 | 85 | 11.8% |
| 30-60k | 373 | 19.6% |
| 60-90k | 882 | 28.6% |
| 90-120k | 991 | 28.7% |
| 120-150k | 777 | 30.9% |
| 150k+ | 1,024 | 31.1% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 2,169 | 26.8% |
| Diesel | 1,974 | 30.3% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,186 | 30.9% |
| 2022 | 940 | 27.2% |
| 2023 | 800 | 27.6% |
| 2024 | 664 | 28.2% |
| 2025 | 553 | 27.3% |
What to check before buying a 2003 ZT
On a 2003 ZT, suspension is what the MOT record says goes wrong most — it appeared in 14.9% of tests. Check these areas before you commit.
- Suspension (14.9% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
- Brakes (13.5% 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 (13.4% 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 2003 MG ZTs pass their MOT?
71.5% of the 4,143 2003 MG ZT MOT tests in this dataset passed — a 28.5% fail rate.
What is the most common MOT failure on a 2003 MG ZT?
Suspension, recorded in 14.9% of tests, followed by brakes (13.5%).
Does the 2003 ZT get worse with mileage?
Its MOT fail rate rises from 11.8% in the 0-30k band to 31.1% in the 150k+ band.
Methodology & source. Based on 4,143 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.