The picture
One Auto: middle-of-the-pack on first-time pass
Across 1,151 MOT tests, the One Auto returns 79.4% first-time pass — roughly in line with the UK fleet average. The single most-logged Major fail is a number-plate lamp out. Windscreen damage and wipers that don't clear the screen round out the top three. Average tested mileage sits at 53,384, 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 rear registration plate lamp or light source missing or inoperative in the case of multiple lamps or light sources
59 occurrences · 5.1% of tests
- 02
Windscreen or window damaged or seriously discoloured but not adversely affecting driver's view
39 occurrences · 3.4% of tests
- 03
Wiper blade missing or obviously not clearing the windscreen
33 occurrences · 2.9% of tests
- 04
Stop lamp with a multiple light source up to 1/2 not functioning
31 occurrences · 2.7% of tests
- 05
A lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
29 occurrences · 2.5% of tests
- 06
a brake lining or pad worn below 1.5mm
16 occurrences · 1.4% of tests
- 07
Windscreen washers not working or not providing sufficient fluid to clear the windscreen
15 occurrences · 1.3% of tests
- 08
Tyre tread depth not in accordance with the requirements
14 occurrences · 1.2% of tests
- 09
A tyre seriously damaged
14 occurrences · 1.2% of tests
- 10
Stop lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
13 occurrences · 1.1% 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
£36–£115
If every one of this One Auto'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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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.
Item 01 · Amazon UK
H7 / W21W bulb pack
A spare-bulb kit lives in the boot. Test morning is not the time to find your stop-lamp's gone.
Search Amazon UK
Item 02 · Amazon UK
Bosch Aerotwin wiper blades
Cheap wipers fail the test on smear streaks. Bosch Aerotwins last a winter and clear a screen properly.
Search Amazon UK
Buying or keeping a One Auto?
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 One Auto 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.