2018 Citroen unknown — MOT failures & pass rate
Across 269 MOT tests analysed for the 2018 Citroen unknown, the most common recorded failure areas were lighting & signalling, visibility and body, structure & corrosion. Its pass rate of 89.2% was in line with the average for cars of a similar age (89.4%). Higher-mileage examples failed more often — 16.7% in the 60-90k group versus 6.0% in the 0-30k group.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 7.1% | 19 |
| 2 | Visibility | 6.3% | 17 |
| 3 | Body, structure & corrosion | 3.7% | 10 |
| 4 | Brakes | 3.0% | 8 |
| 5 | Suspension | 1.5% | 4 |
| 6 | Emissions & environmental | 1.1% | 3 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 17 |
| 2 | Position lamp | 8 |
| 3 | Headlamp aim | 7 |
| 4 | Washers | 6 |
| 5 | Joints | 6 |
| 6 | Stop lamp | 3 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 13.0% | 35 |
| 2 | Brakes | 4.5% | 12 |
| 3 | Other defects | 4.1% | 11 |
| 4 | Emissions & environmental | 3.7% | 10 |
| 5 | Visibility | 3.4% | 9 |
| 6 | Suspension | 3.0% | 8 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 184 | 6.0% |
| 30-60k | 40 | 20.0% |
| 60-90k | 30 | 16.7% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 234 | 9.4% |
| Petrol | 35 | 20.0% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 81 | 9.9% |
| 2022 | 46 | 6.5% |
| 2023 | 57 | 14.0% |
| 2024 | 33 | 12.1% |
| 2025 | 52 | 11.5% |
What to check before buying a 2018 unknown
Before buying a 2018 Citroen unknown, focus on the areas it most often fails on. Lighting & signalling accounted for 7.1% of tests for this year.
- Lighting & signalling (7.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Visibility (6.3% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
- Body, structure & corrosion (3.7% of tests): The one to take seriously on older cars — corrosion to structural areas can be costly and is an MOT failure. Typical repair: £200–£1,500+.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2018 Citroen unknowns pass their MOT?
89.2% of the 269 2018 Citroen unknown MOT tests in this dataset passed — a 10.8% fail rate.
What is the most common MOT failure on a 2018 Citroen unknown?
Lighting & signalling, recorded in 7.1% of tests, followed by visibility (6.3%).
Does the 2018 unknown get worse with mileage?
Its MOT fail rate rises from 6.0% in the 0-30k band to 16.7% in the 60-90k band.
Methodology & source. Based on 269 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.