The picture
Db9: a strong MOT record by UK norms
Across 4,692 MOT tests, the Db9 returns 89.8% first-time pass — comfortably ahead of the UK fleet average. The single most-logged Major fail is a lamp out. The engine warning light staying lit and windscreen damage round out the top three. Average tested mileage sits at 39,379, 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 lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
65 occurrences · 1.4% of tests
- 02
Engine MIL illuminated indicating a malfunction
50 occurrences · 1.1% of tests
- 03
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
49 occurrences · 1.0% of tests
- 04
A spring or spring component fractured or seriously weakened
47 occurrences · 1.0% of tests
- 05
Wiper blade missing or obviously not clearing the windscreen
41 occurrences · 0.9% of tests
- 06
Wiper blade defective
38 occurrences · 0.8% of tests
- 07
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
34 occurrences · 0.7% of tests
- 08
A tyre seriously damaged
33 occurrences · 0.7% of tests
- 09
The aim of a headlamp is not within limits laid down in the requirements
28 occurrences · 0.6% of tests
- 10
Significant brake effort recorded with no brake applied indicating a binding brake
26 occurrences · 0.6% 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 2 failures
£100–£285
If every one of this Db9'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 →
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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 Db9?
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 Db9 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.