The picture
523: middle-of-the-pack on first-time pass
Across 3,059 MOT tests, the 523 returns 73.0% first-time pass — below the UK fleet average. The single most-logged Major fail is a defective headlamp lens. A torn suspension dust cover and windscreen damage round out the top three. Average tested mileage sits at 116,239, 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
Headlamp reflector or lens slightly defective
115 occurrences · 3.8% of tests
- 02
A suspension joint dust cover severely deteriorated
87 occurrences · 2.8% of tests
- 03
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
81 occurrences · 2.6% of tests
- 04
Parking brake efficiency below minimum requirement
79 occurrences · 2.6% of tests
- 05
A suspension joint dust cover missing or no longer prevents the ingress of dirt etc
79 occurrences · 2.6% of tests
- 06
A rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
78 occurrences · 2.5% of tests
- 07
Tyre tread depth not in accordance with the requirements
77 occurrences · 2.5% of tests
- 08
A suspension joint dust cover severely deteriorated
72 occurrences · 2.4% of tests
- 09
A spring or spring component fractured or seriously weakened
70 occurrences · 2.3% of tests
- 10
The aim of a headlamp is not within limits laid down in the requirements
67 occurrences · 2.2% 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
£170–£560
If every one of this 523'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 523?
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 523 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.