1992 Mercedes-Benz 500 — MOT failures & pass rate
Across 499 MOT tests, the 1992 Mercedes-Benz 500 recorded an 87.8% pass rate. That is 10.7 percentage points better than all cars of a similar age, which fail at 22.9%. Failures cluster in lighting & signalling, emissions & environmental and brakes.
What the MOT record shows
One area stands out: lighting & signalling, recorded in 7.4% of tests against 3.6% for the next-worst category.
At component level the recurring items are catalyst emissions, headlamp aim and position lamp — catalyst emissions alone was recorded 17 times.
Condition tracks the odometer closely. Failures run at 11.4% in the 0-30k band and 19.0% in the 150k+ band, a 7.6-point spread.
Brakes is the most common advisory, noted on 19.2% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 7.4% | 37 |
| 2 | Emissions & environmental | 3.6% | 18 |
| 3 | Brakes | 3.0% | 15 |
| 4 | Suspension | 2.4% | 12 |
| 5 | Body, structure & corrosion | 2.2% | 11 |
| 6 | Visibility | 2.0% | 10 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Catalyst emissions | 17 |
| 2 | Headlamp aim | 16 |
| 3 | Position lamp | 9 |
| 4 | Stop lamp | 8 |
| 5 | Washers | 8 |
| 6 | Rear fog lamp | 6 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 19.2% | 96 |
| 2 | Suspension | 15.4% | 77 |
| 3 | Emissions & environmental | 11.0% | 55 |
| 4 | Tyres | 10.0% | 50 |
| 5 | Steering | 9.6% | 48 |
| 6 | Body, structure & corrosion | 4.6% | 23 |
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 | 44 | 11.4% |
| 30-60k | 51 | 9.8% |
| 60-90k | 147 | 12.2% |
| 90-120k | 125 | 9.6% |
| 120-150k | 74 | 13.5% |
| 150k+ | 58 | 19.0% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 108 | 12.0% |
| 2022 | 106 | 9.4% |
| 2023 | 103 | 13.6% |
| 2024 | 98 | 14.3% |
| 2025 | 84 | 11.9% |
What to check before buying a 1992 500
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 7.4% of tests. Start there.
- Lighting & signalling (7.4% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Emissions & environmental (3.6% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Brakes (3.0% 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.
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 1992 Mercedes-Benz 500s pass their MOT?
87.8% of the 499 1992 Mercedes-Benz 500 MOT tests in this dataset passed — a 12.2% fail rate.
What is the most common MOT failure on a 1992 Mercedes-Benz 500?
Lighting & signalling, recorded in 7.4% of tests, followed by emissions & environmental (3.6%).
Does the 1992 500 get worse with mileage?
Its MOT fail rate rises from 11.4% in the 0-30k band to 19.0% in the 150k+ band.
Methodology & source. Based on 499 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.