2015 Mercedes-Benz Viano — MOT failures & pass rate
The 2015 Mercedes-Benz Viano passed 78.6% of its 897 recorded MOT tests. That is 5.2 percentage points worse than all cars of a similar age, which fail at 16.2%. Failures cluster in lighting & signalling, brakes and tyres.
What the MOT record shows
No single area dominates — lighting & signalling (9.5%) and brakes (8.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are rbt (sp), headlamp aim and side repeaters — rbt (sp) alone was recorded 41 times.
Mileage is the strongest signal on the record: 6.0% of 0-30k cars fail, rising to 24.8% once past 150k — 4.1× the risk.
Advisories point at the next bill rather than this one: tyres was flagged on 24.3% of tests without failing them.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 9.5% | 85 |
| 2 | Brakes | 8.1% | 73 |
| 3 | Tyres | 5.7% | 51 |
| 4 | Emissions & environmental | 4.9% | 44 |
| 5 | Suspension | 4.2% | 38 |
| 6 | Visibility | 3.6% | 32 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Rbt (sp) | 41 |
| 2 | Headlamp aim | 32 |
| 3 | Side repeaters | 31 |
| 4 | On or after 01/01/2014 | 31 |
| 5 | Tread depth | 30 |
| 6 | Wipers | 20 |
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 | 24.3% | 218 |
| 2 | Brakes | 19.5% | 175 |
| 3 | Suspension | 14.4% | 129 |
| 4 | Other defects | 9.3% | 83 |
| 5 | Body, structure & corrosion | 6.9% | 62 |
| 6 | Lighting & signalling | 6.2% | 56 |
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 | 50 | 6.0% |
| 30-60k | 157 | 21.7% |
| 60-90k | 167 | 23.4% |
| 90-120k | 133 | 21.1% |
| 120-150k | 95 | 15.8% |
| 150k+ | 294 | 24.8% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 863 | 20.9% |
| Petrol | 34 | 35.3% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 212 | 21.2% |
| 2022 | 178 | 23.6% |
| 2023 | 181 | 21.0% |
| 2024 | 168 | 20.8% |
| 2025 | 158 | 20.3% |
What to check before buying a 2015 Viano
On a 2015 Viano, lighting & signalling is what the MOT record says goes wrong most — it appeared in 9.5% of tests. Check these areas before you commit.
- Lighting & signalling (9.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (8.1% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Tyres (5.7% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
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 2015 Mercedes-Benz Vianos pass their MOT?
78.6% of the 897 2015 Mercedes-Benz Viano MOT tests in this dataset passed — a 21.4% fail rate.
What is the most common MOT failure on a 2015 Mercedes-Benz Viano?
Lighting & signalling, recorded in 9.5% of tests, followed by brakes (8.1%).
Does the 2015 Viano get worse with mileage?
Its MOT fail rate rises from 6.0% in the 0-30k band to 24.8% in the 150k+ band.
Methodology & source. Based on 897 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.