2025 MOT results
Toyota Prius common problems
The most common reason a Toyota Prius fails its MOT is a sidelight out, on 15.5% of its 34,788 failed tests in 2025. Against other cars of the same age, 4 faults stand out, the widest gaps being: a number plate lamp out at 11.9% of failures against 3.5% expected; a rear fog lamp out at 4.4% of failures against 1.3% expected; a split joint boot at 6.7% of failures against 2.9% expected.
- Tests in 2025 162,805 Cars aged three and over
- Failed first time 21.4% 34,788 tests
- Found a dangerous defect 5.1% Unsafe to drive away
- Ended with an advisory 37.7% A problem to watch, not a failure
What fails a Toyota Prius MOT
Each bar is the share of failed Toyota Prius tests with that defect. Where we can compare it with cars of the same registration years, the marker shows what an average car of those ages records (12 of the 12 items below).
Most common reasons for failure
A test can fail for more than one defect, so shares add up to more than 100%.
| Defect | Share of failed tests |
|---|---|
| Position lamp: not working Lamps, reflectors and electrical equipment | 15.5% |
| Registration plate lamp(s): inoperative in the case of a single lamp or all lamps Lamps, reflectors and electrical equipment | 11.9% |
| Wipers: does not clear the windscreen effectively Visibility | 9.2% |
| Tyres: tread depth below requirements of 1.6mm Tyres | 8.7% |
| Linkage ball joint dust cover no longer prevents the ingress of dirt Suspension | 6.7% |
| Brake pads: less than 1.5 mm thick Brakes | 6.2% |
| Malfunction indicator lamp: inoperative or indicates a malfunction Noise, emissions and leaks | 5.8% |
| Headlamp: not working on dipped beam Lamps, reflectors and electrical equipment | 5.8% |
| Headlamp aim: projected beam image is obviously incorrect Lamps, reflectors and electrical equipment | 5.0% |
| Washers: provides insufficient washer liquid Visibility | 4.9% |
| Rear fog lamp: not working Lamps, reflectors and electrical equipment | 4.4% |
| Shock absorbers: serious fluid leak Suspension | 4.2% |
Source:DVSA,UK Motoring analysis 2025 Updated
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Sidelight out
15.5% of failures 8.5% expected 1.8 times as often
A sidelight, also called a position lamp, not working. It marks the width of the car at night.
Walk round the car with the lights on and the hazards going; these are the cheapest failures to avoid.
-
Number plate lamp out
11.9% of failures 3.5% expected 3.4 times as often
The lamp over the rear number plate not working, so the plate cannot be read at night.
Walk round the car with the lights on and the hazards going; these are the cheapest failures to avoid.
-
Wiper blades that do not clear the screen
9.2% of failures 6.3% expected 1.5 times as often
Wiper blades that leave the windscreen smeared or streaked across the area the driver looks through.
Look for split or hardened rubber, and lift each blade to see whether it still sits flat.
-
Tyre worn below the legal limit
8.7% of failures 8.3% expected about as expected
A tyre worn past the 1.6mm legal minimum across the middle three quarters of the tread.
A 20p coin in the main grooves: if the outer band of the coin is visible, the tyre is close to the limit.
-
Split joint boot
6.7% of failures 2.9% expected 2.3 times as often
A split rubber boot on a joint or driveshaft. The joint may still be sound, but dirt and water get in once the boot is open.
Turn the wheels to full lock and look behind them for greasy splits in the rubber concertina.
-
Worn brake pads
6.2% of failures 6.6% expected about as expected
Friction material worn under 1.5mm, thinner than the point most manufacturers call the limit.
Look through the wheel spokes at the pad against the disc; wear indicators squeal before they get this far.
Which parts of the car fail
Lamps, reflectors and electrical equipment is the area that most often fails a Toyota Prius, on 52.4% of failed tests. That is also where it differs most from cars of the same registration years, which record 37.3%.
Failure categories
DVSA's own sections of the test. The marker is what cars of the same registration years record.
| Defect category | Share of failed tests |
|---|---|
| Lamps, reflectors and electrical equipment | 52.4% |
| Suspension | 23.9% |
| Tyres | 21.0% |
| Visibility | 17.2% |
| Brakes | 17.0% |
| Body, chassis, structure | 7.0% |
| Noise, emissions and leaks | 6.2% |
| Steering | 3.3% |
Source:DVSA,UK Motoring analysis 2025 Updated
What testers warn about
37.7% of Toyota Prius tests ended with at least one advisory: a fault the tester found that did not fail the test. On Toyota Priuses, these are the items to ask about on a car you are viewing, because they are what the last tester expected to go next.
Most common advisories
Share of all tests, passes included.
| Advisory | Share of tests |
|---|---|
| Tread depth: worn close to legal limit or worn on edge Tyres | 13.1% |
| Brake discs: worn, pitted or scored, but not seriously weakened Brakes | 6.2% |
| Brake pads: wearing thin Brakes | 5.2% |
| Tyres: slightly damaged or cracking or perishing Tyres | 5.0% |
| Rigid brake pipes: corroded, covered in grease or other material Brakes | 3.9% |
| Suspension arms: pin or bush worn but not resulting in excessive movement Suspension | 3.5% |
| Registration plates: deteriorated but not likely to be misread Identification of the vehicle | 3.3% |
| Headlamp: product on the lens but not seriously reducing light output Lamps, reflectors and electrical equipment | 2.9% |
| Shock absorbers: light misting of oil Suspension | 2.4% |
| Play in steering rack inner joint(s) Non-component advisories | 2.0% |
| Brake discs: worn, but not excessively Brakes | 2.0% |
| Coil spring: corroded Suspension | 2.0% |
Source:DVSA,UK Motoring analysis 2025 Updated
What changes as a Toyota Prius gets older
A 2021 Toyota Prius failed 7.9% of its MOT tests in 2025; a 2005 one failed 37.9%. What fails changes as much as how often, and these are the two years themselves rather than an average across them.
2021 Toyota Prius 7.9% failed, from 3,199 tests
- Wiper blades that do not clear the screen 20.9%
- Tyre worn below the legal limit 13.4%
- Cut tyre 8.3%
- Rear fog lamp out 7.9%
- Tyre worn through to the cords 7.9%
- Number plate lamp out 5.9%
2005 Toyota Prius 37.9% failed, from 2,078 tests
- Sidelight out 24.3%
- Engine management light on 14.9%
- Headlamp out 8.9%
- Broken coil spring 8.4%
- Headlamp aim out of line 8.3%
- Number plate lamp out 7.1%
Shares are of each year's failed tests. Every MOT a particular car has had, with the defects and advisories written at each test, is on GOV.UK's MOT history service from the registration, free.
Toyota Prius problems: common questions
What is the most common problem with a Toyota Prius?
Of the faults that fail an MOT, “Position lamp: not working” is the most common: it appears on 15.5% of failed Toyota Prius tests. Across categories, lamps, reflectors and electrical equipment is the area that most often fails one, on 52.4% of failed tests.
How often does a Toyota Prius fail its MOT?
21.4% of Toyota Prius tests in 2025 were not passed first time, from 162,805 tests of cars aged three and over. Allowing for the age and mileage of the cars tested, that gives it a UK Motoring Reliability Score of 64 out of 100, where 50 is as expected.
Does anything fail more often on a Toyota Prius than on other cars?
Yes. “Registration plate lamp(s): inoperative in the case of a single lamp or all lamps” appears on 11.9% of its failures against 3.5% for cars of the same age, and “Rear fog lamp: not working” appears on 4.4% of its failures against 1.3% for cars of the same age. Where an item is missing from the national figures for a year, we use the smallest share those figures show, so the comparison never overstates the difference.
Are these the same as breakdowns or known faults?
No. These are the items a tester recorded at the MOT, which covers condition and safety: lamps, brakes, tyres, suspension, corrosion and emissions. A gearbox that is unpleasant, an infotainment screen that has died, or a car that will not start on a cold morning are not part of the test, so they are not in these figures.
Where do the figures come from?
Every normal MOT test of a Toyota Prius aged three and over in Great Britain in 2025, from DVSA's anonymised MOT results. Retests are excluded, and the same fault on more than one wheel counts once.
Data stories to read next
Data sources and methodology
| Figures | Source | Period | Records | Updated |
|---|---|---|---|---|
| MOT defects and advisories | Anonymised MOT tests and results Driver and Vehicle Standards Agency Derived statistics UK Motoring | 2025 | 162,805 MOT tests | 19 September 2026 |
- Shares for defects are of failed tests; shares for advisories are of all tests. A test can carry several defects, so shares add to more than 100%.
- The expected share is what an average car of the same registration years records, weighted by where this model’s failures fall. Where an item is outside the national figures for a year, the smallest share those figures show is used in its place, which is an upper bound, so the comparison never overstates a model’s problems. No expectation is published where less than 80% of the model’s failures can be compared.
- Great Britain only: DVSA does not run MOT testing in Northern Ireland. Cars under three years old are not tested.
- The descriptions of what each part does are general and the same on every model. Every figure comes from the MOT data.
Contains public sector information licensed under the Open Government Licence v3.0.