Mercedes-Benz SLK MOT pass rate and common problems
78.9% of 105,495 Mercedes-Benz SLK MOT tests pass.
At 78.9%, the SLK passes slightly less often than the average across all Mercedes-Benz models (83.5%).
The Mercedes-Benz SLK's pass rate of 78.9% is in line with the national average for cars, at 79.2%.
Own this Mercedes-Benz SLK?
This is the average across every Mercedes-Benz SLK in the dataset. Look up your own registration for its actual MOT history, and a free place to keep its maintenance records.
Have service invoices? Upload and keep them with your car’s history →
How to check and keep your Mercedes-Benz’s service history →
Pass rate by vehicle age
Pass rate declines noticeably with age, from 85.9% at 6–10 years to 75.5% at 15+ years.
| Vehicle age | Pass rate | Tests | Average mileage |
|---|---|---|---|
| 0–3 years | no tests recorded | 0 | no reading |
| 3–6 years | too few tests (2) | 2 | no reading |
| 6–10 years | 85.9% | 16,542 | 48,179 miles |
| 10–15 years | 80.8% | 35,065 | 62,388 miles |
| 15+ years | 75.5% | 53,886 | 82,196 miles |
Common MOT failure reasons for the Mercedes-Benz SLK
The most common reason the Mercedes-Benz SLK fails its MOT is suspension — present in 47.9% of failed tests, most often logged as "Fractured or broken".
| Category | Share of failed tests | Example |
|---|---|---|
| Suspension | 47.9% | Fractured or broken |
| Lamps, reflectors and electrical equipment | 39.2% | Not working |
| Brakes | 29.4% | Excessively corroded |
| Tyres | 23.4% | Tread depth below requirements of 1.6mm |
| Visibility | 11.2% | Does not clear the windscreen effectively |
| Noise, emissions and leaks | 10.5% | Inoperative or indicates a malfunction |
| Body, chassis, structure | 5.0% | Has a major leak of exhaust gases |
| Seat belts and supplementary restraint systems | 3.9% | Warning lamp indicates a fault |
| Steering | 3.3% | Ball joint has excessive play |
| Road Wheels | 1.7% | Fixing missing |
Buying a used Mercedes-Benz SLK: what to check
These checks follow the Mercedes-Benz SLK’s own MOT record: the areas it fails on most often, and how that changes as the car gets older. None of them replaces a mechanic’s inspection, but they tell you where to look first.
The biggest drop in pass rate for the Mercedes-Benz SLK comes between 10–15 years and 15+ years old, from 80.8% to 75.5%. If you are looking at one in or just past that range, read its MOT history closely.
By mileage, the steepest fall is from 30,000–60,000 mi to 60,000–90,000 mi: 84.2% down to 76.7%. Mileage matters as well as age, so compare the car’s recorded mileages with its year.
1. Suspension
Recorded in 47.9% of failed Mercedes-Benz SLK MOTs. 13.6% of tests at 15+ years failed on suspension, against 6.3% at 6–10 years.
Listen for knocks over bumps and speed humps, and check the car sits level. Push down on each corner: it should settle rather than keep bouncing.
2. Lights and electrics
Recorded in 39.2% of failed Mercedes-Benz SLK MOTs. 15.5% of tests at 15+ years failed on lights and electrics, against 2.6% at 6–10 years.
Walk round with the lights on: headlights (dipped and main), indicators, brake lights, fog light and number-plate lamp. Check the dashboard warning lights come on with the ignition, then go out once the engine starts.
3. Brakes
Recorded in 29.4% of failed Mercedes-Benz SLK MOTs. 9.5% of tests at 15+ years failed on brakes, against 2.7% at 6–10 years.
On the test drive, the car should stop straight without pulling or juddering, and the handbrake should hold it on a slope. Look through the wheels for scored or heavily lipped discs.
4. Tyres
Recorded in 23.4% of failed Mercedes-Benz SLK MOTs.
Check tread depth across the whole width of every tyre, including the inner edge. Uneven wear can point to alignment or suspension problems. Look for cuts and bulges in the sidewalls.
5. Windscreen and wipers
Recorded in 11.2% of failed Mercedes-Benz SLK MOTs. 4.1% of tests at 15+ years failed on windscreen and wipers, against 1.0% at 6–10 years.
Look for windscreen chips and cracks in the driver’s line of sight, and check the wipers clear the screen and the washers work.
Check the car’s own MOT history. Averages describe the model, not the car in front of you. Look up its registration for past failures, advisories that were never fixed, and gaps or dips in the recorded mileage.
Ask for the service history. Invoices show what was done and when; a stamp alone shows less. See how to check Mercedes-Benz service history and what a service history check can tell you.
Related Mercedes-Benz models
- Mercedes-Benz Cla — 87.2% pass rate
- Mercedes-Benz Vito — 75.2% pass rate
- Mercedes-Benz B-Class — 79.0% pass rate
- Mercedes-Benz Gle — 91.9% pass rate
- Mercedes-Benz ML — 80.7% pass rate
- Mercedes-Benz S-Class — 88.9% pass rate
Frequently asked questions
- What is the MOT pass rate for the Mercedes-Benz SLK?
- 78.9% of Mercedes-Benz SLK MOT tests pass, based on 105,495 tests in the DVSA anonymised MOT tests and results dataset.
- What are the most common MOT failures for the Mercedes-Benz SLK?
- The most common reason the Mercedes-Benz SLK fails its MOT is suspension — present in 47.9% of failed tests, most often logged as "Fractured or broken".
- What are the common problems with the Mercedes-Benz SLK?
- Going by its MOT results, the most common problem areas on the Mercedes-Benz SLK are suspension; lights and electrics; brakes. 13.6% of tests at 15+ years failed on suspension, against 6.3% at 6–10 years.
- What should I check when buying a used Mercedes-Benz SLK?
- Start with the areas it most often fails its MOT on: suspension; lights and electrics; brakes; tyres; windscreen and wipers. Then check the specific car's MOT history by registration for failures, advisories and mileage, and ask the seller for service invoices.
- Does this show the Mercedes-Benz SLK's service history?
- No — this is MOT test data, which covers roadworthiness, not servicing. A service history is a separate record of maintenance work, which a specific car only has if its owner has kept it. See the Mercedes-Benz service history guide for how to check and keep one.