Proton Jumbuck MOT pass rate & common failures
3,633 MOT tests on the Proton Jumbuck (2003–2007) give it a 70.4% pass rate. Against all cars of a similar age (27.5% fail rate), the Jumbuck comes out 2.1pp worse. Its most common failure areas are lighting & signalling, suspension and emissions & environmental.
What the MOT record shows
No single area dominates — lighting & signalling (14.7%) and suspension (13.4%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are component mounting prescribed areas, catalyst emissions and prescribed areas — component mounting prescribed areas alone was recorded 520 times.
Mileage is the strongest signal on the record: 24.9% of 0-30k cars fail, rising to 34.6% once past 150k.
Advisories point at the next bill rather than this one: brakes was flagged on 28.8% of tests without failing them.
How it compares
By model year
Every Jumbuck model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 2003 | 497 | 69.4% | 30.6% | Lighting & signalling |
| 2004 | 1,135 | 69.3% | 30.7% | Lighting & signalling |
| 2005 | 735 | 72.0% | 28.0% | Lighting & signalling |
| 2006 | 1,263 | 70.9% | 29.1% | Lighting & signalling |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 14.7% | 535 |
| 2 | Suspension | 13.4% | 487 |
| 3 | Emissions & environmental | 11.0% | 399 |
| 4 | Brakes | 10.9% | 395 |
| 5 | Body, structure & corrosion | 9.4% | 340 |
| 6 | Visibility | 5.6% | 203 |
| 7 | Steering | 5.3% | 193 |
| 8 | Seat belts & restraints | 5.1% | 186 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Component mounting prescribed areas | 520 |
| 2 | Catalyst emissions | 387 |
| 3 | Prescribed areas | 289 |
| 4 | Rigid brake pipes | 223 |
| 5 | Wipers | 188 |
| 6 | Headlamp aim | 182 |
| 7 | Service brake imbalance | 171 |
| 8 | Exhaust system | 162 |
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 | 28.8% | 1,048 |
| 2 | Suspension | 28.5% | 1,035 |
| 3 | Emissions & environmental | 23.0% | 836 |
| 4 | Tyres | 21.7% | 788 |
| 5 | Body, structure & corrosion | 18.4% | 667 |
| 6 | Lighting & signalling | 13.6% | 494 |
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 | 257 | 24.9% |
| 30-60k | 1,144 | 27.5% |
| 60-90k | 1,377 | 29.9% |
| 90-120k | 618 | 32.4% |
| 120-150k | 181 | 35.9% |
| 150k+ | 52 | 34.6% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 953 | 29.2% |
| 2022 | 834 | 30.8% |
| 2023 | 726 | 28.8% |
| 2024 | 592 | 29.9% |
| 2025 | 528 | 29.2% |
What to check before buying a Proton Jumbuck
- Lighting & signalling (14.7% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (13.4% 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.
- Emissions & environmental (11.0% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
What is the MOT pass rate for the Proton Jumbuck?
70.4% of the 3,633 Proton Jumbuck MOT tests in this dataset passed, a 29.6% fail rate, across model years 2003–2007.
What does the Proton Jumbuck most often fail its MOT on?
Lighting & signalling, recorded in 14.7% of tests, then suspension (13.4%).
How much does mileage affect Jumbuck MOT results?
Fail rates run at 24.9% for cars in the 0-30k band and 34.6% for 150k+, a 9.7-point difference.
Methodology & source. Based on 3,633 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.