At a glance
How 5,108 first tests went in 2025.
- Passed first time
- 71 in every 100
- Did not pass first time
- 29 in every 1001,488 failed first-attempt tests
- The typical car
- 7 yearsabout 48,834 miles
- First tests counted
- 5,108
What failed most often
- Tyre tread depth (front)9 in every 100 failed tests
- Windscreen wipers (front)9 in every 100 failed tests
- Drive shaft joints and boots (front)8 in every 100 failed tests
How we count this. Data: UK MOT open data, 2025. Only Class 4 cars on their first MOT of the year are counted. A car that fails and is fixed at the test station still counts as a fail in the first-attempt rate. These are raw results, not adjusted for age, mileage, or peer mix. The MOT does not test engine or gearbox internals.
These are patterns across 2018 Citroen C4 Cactus vehicles in 2025, not a prediction that any one car will have them. Faults are grouped by part of the car. A wear pattern follows age and use more than the way the car was built. They come from MOT defect codes, not manufacturer bulletins, recalls or a diagnosis of any one car.
Body and structure
Two faults. The strongest is the exhaust system (front): 7.4 times as often as on similar cars.
Figures below are measured across the 1,488 failed first attempts in 2025 that had a mileage recorded, which allows a like-for-like comparison.
We only list faults with at least 20 failures and a rate of about 2.0 times that of similar cars, which keeps one-off results out of the list.
Exhaust system (front)
What it means
Exhaust fumes causing a danger to health of persons on board are graded Dangerous, and so is a silencer likely to become detached. Fumes entering the cabin are Major. One or more missing or defective mountings does not necessarily make the exhaust insecure, since testers assess the overall security of the system.
Also noted as an advisory
Testers also noted it as an advisory, worn but not yet failing, on 120 first tests, 11 times as often as on similar cars.
Drive shaft joints and boots (front)
Data: UK MOT open data, 2025. Compared with cars of the same age and mileage. Advisories count notes recorded on failed first tests only.
Lamps and electrical
Two faults and one wear pattern. The strongest is the number plate lights (rear): 4.8 times as often as on similar cars.
Number plate lights (rear)
What it means
Registration plate lamps must light up the rear registration plate and operate at the same time as the position lamps. A missing or inoperative lamp is Major when the plate has only one lamp or all its lamps are not working, and Minor when the plate has several lamps or light sources and not all have failed. A lamp throwing direct white light to the rear is also Minor.
Headlight aim not tested
What it means
Headlamp aim recorded as not tested, or unable to be tested, is a Major failure. These results must only be used where it becomes apparent during the test that the item cannot be tested, and this could not have been identified before starting. The reason must be included in the additional information box.
Headlight (front)
What it means
On vehicles first used on or after a set date, a halogen headlamp unit converted to take HID or LED bulbs fails for light source and lamp not compatible, which is Major. A complete unit built with those light sources is not failed for that. The precise position of the lamps is not part of the inspection beyond a visual look to see that they sit at about the same height and distance from each side.
Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.
Suspension
One fault: suspension arm ball joint (front), 3.5 times as often as on similar cars.
Suspension arm ball joint (front)
What it means
A suspension arm ball joint is failed under the general suspension pin, bush or joint wording. Excessively worn is Major, and likely to become detached is graded Dangerous.
Also noted as an advisory
Testers also noted it as an advisory, worn but not yet failing, on 28 first tests, 2.2 times as often as on similar cars.
Data: UK MOT open data, 2025. Compared with cars of the same age and mileage. Advisories count notes recorded on failed first tests only.
Noise, emissions and leaks
One fault: petrol emissions (with catalyst), 2.1 times as often as on similar cars.
Petrol emissions (with catalyst)
What it means
Emissions levels over the manufacturer's specified limits are Major, as are levels over default limits, which apply when no exact match is found for the vehicle. Dense blue or clearly visible black smoke at idle, held for a set period, is Major, except for certain older vehicles and two stroke engines where smoke is unavoidable. An induction or exhaust leak that could affect emissions levels is Major too.
Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.
Visibility
One fault: windscreen wipers (front), 2.0 times as often as on similar cars.
Windscreen wipers (front)
Data: UK MOT open data, 2025. Compared with cars of the same age and mileage.
Advisories
Other things testers noted as worn or close to failing, more often than on similar cars.
An advisory is a note from the tester about something that has not failed yet. It is an early warning, not a fail. Advisories for the faults above are shown with those faults.
Exhaust system (rear)
Coil spring (rear)
Suspension arm pins and bushes (front)
Brake performance (roller test, front)
Data: UK MOT open data, 2025. Counts cover advisories recorded on failed first tests only, compared with cars of the same age and mileage.
MOT pass rates
How first tests ended, and how the pass rates are counted.
- Passed first time
- 71in every 100
- Passed on the first test.
- Fixed at the station
- 7in every 100
- Failed, then fixed at the test station the same day.
- Failed
- 22in every 100
- Did not pass, and were not fixed at the test station.
First-attempt pass 70.9% of 5,108 first tests (2025): only cars that passed first time count. Official-style pass 77.9%: cars fixed at the test station also count as a pass. The 7 fixed and the 22 not fixed make the 29 in every 100 that did not pass first time.
Petrol and diesel
Figures are in every 100 first tests. Cars with more miles usually fail more often, so the same-mileage figure gives every fuel the mileage mix of all the cars in this year.
Same model, other years
Passed first time in every 100, all tested in 2025.
Newer cars are younger, so look for a jump rather than the climb. A year earlier (2024), when these cars were a year younger, 74 in every 100 passed first time.
| Year | Passed first time | First tests |
|---|---|---|
| 2015 | 56 in every 100 | 366 |
| 2016 | 62 in every 100 | 3,322 |
| 2017 | 66 in every 100 | 5,532 |
| 2018 This car | 71 in every 100 | 5,108 |
| 2019 | 75 in every 100 | 3,716 |
| 2020 | 81 in every 100 | 1,838 |
| 2021 | 84 in every 100 | 308 |
If you are buying one
What this year's MOT record means for the decision in front of you.
Mileage matters most on a 2018 Citroen C4 Cactus.
Of 2018 Citroen C4 Cactus vehicles with under 34,000 miles, 82 in every 100 passed their 2025 MOT first time. With 65,000 miles or more, 62 in every 100 did.
What to check at your mileage
How often each fault turned up on a failed first test, by the car's mileage. Read it as: what is likely to need looking at on a car like the one in front of you.
| Under 34,000 | 44,000–54,000 | 65,000 and over | |
|---|---|---|---|
| Tyre tread depth (front) | 1.1 | 3.1 | 4.7 |
| Windscreen wipers (front) | 2.4 | 2.9 | 2.6 |
| Drive shaft joints and boots (front) | 2.5 | 2.3 | 1.8 |
| Suspension arm ball joint (front) | 0.4 | 2.9 | 4.5 |
| Headlight | 0.4 | 3.0 | 3.0 |
Faults per 100 first tests, by the car's mileage at the test.
When a car fails
of failed cars had one item to fix.
of failed cars had three or more items to fix.
of all first tests had a defect the tester marked dangerous (unsafe to drive away).
Every figure here is a first-attempt MOT rate from DVSA open data for this model line, for cars of this model year tested in 2025. Each mileage band holds a fifth of the tests. MOTs do not test engine or gearbox internals, so this is a pre-purchase checklist, not a full reliability score.
FAQs
Short answers about how to read this model-year guide.
About this data
How this page is built and what it can (and can't) say.
These figures come from UK MOT open data for this model year. We surface common failure patterns against similar cars, not a full reliability score, and not a pass/fail verdict on any individual vehicle.
What we include
UK Class 4 cars only. Normal MOT tests (not retests); first test per vehicle per calendar year; results pass, PRS, or fail.
Same-day repairs
PRS means the car failed items that were fixed at the test station and then passed the same day. We count PRS as a first-attempt fail in headline rates so same-day repairs do not hide problems.
How we compare
We compare this model year with other Class 4 cars of similar age and mileage in the same test year. This model family is left out of the peer group so the car is not measured against itself.
What this does not cover
- MOTs do not cover engine internals, gearboxes, or many electronics; this is not a full reliability score.
- Common faults come from MOT defect stats, not manufacturer TSBs or recalls.
- Age and mileage matching reduces, but does not remove, differences in how cars were used and maintained.
- If the data for a car is too thin to say anything useful, we say so rather than guess.
Contains public sector information licensed under the Open Government Licence v3.0.
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