The picture
Mx-5: middle-of-the-pack on first-time pass
Across 112,297 MOT tests, the Mx-5 returns 77.0% first-time pass — roughly in line with the UK fleet average. The single most-logged Major fail is a torn suspension dust cover. A broken or weak spring and the strength or continuity of the load bearing round out the top three. Average tested mileage sits at 65,998, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.
Top ten reasons for rejection.
- 01
A suspension joint dust cover severely deteriorated
4,210 occurrences · 3.7% of tests
- 02
A spring or spring component fractured or seriously weakened
3,578 occurrences · 3.2% of tests
- 03
The strength or continuity of the load bearing structure within 30cm of any sub-frame, spring or suspension component mounting (a 'prescribed area') is significantly reduced or inadequately repaired
3,573 occurrences · 3.2% of tests
- 04
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
2,656 occurrences · 2.4% of tests
- 05
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
2,608 occurrences · 2.3% of tests
- 06
The strength or continuity of the load bearing structure within 30cm of any seat belt anchorage (a 'prescribed area') is significantly reduced or inadequately repaired
2,363 occurrences · 2.1% of tests
- 07
Significant brake effort recorded with no brake applied indicating a binding brake
2,291 occurrences · 2.0% of tests
- 08
Headlamp reflector or lens slightly defective
2,225 occurrences · 2.0% of tests
- 09
Lambda coefficient outside the default limits or the range specified by the manufacturer
1,863 occurrences · 1.7% of tests
- 10
Wiper blade missing or obviously not clearing the windscreen
1,854 occurrences · 1.7% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Worst-case fix budget · top 3 failures
£168–£515
If every one of this MX 5's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
Try the calculator
Build your own retest budget.
Tools that pre-empt a retest.
Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.
Buying or keeping a MX 5?
Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a MX 5 and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.