Mercedes-Benz Slk MOT Failure Rate & Common Faults
We analysed 59,347 MOT tests on the Mercedes-Benz Slk carried out in 2023. 27% failed at the first attempt, which is roughly in line with the 29% average across all cars in the same data. Put another way, about 7 in 10 Slks passed first time.
Results cover cars first registered from 1997 to 2016. Compared with other cars of the same age, 2011 models did best (77% passed, +14.4 points against the average for 12-year-old cars), while 1997 models fared worst (68%, +3.5 points). Tested cars had covered 68,471 miles on average, against 73,145 across all cars.
The most common reason for failure was suspension, found on 11.0% of tests (slightly above the 8.9% seen across all cars). The single most frequent fault was "fractured or broken", on 5.1% of tests.
- MOT tests analysed
- 59,347
- First-time pass rate
- 73%
- All cars: 71%
- Versus all cars
- +1.2 points
- Average mileage at test
- 68,471
- All cars: 73,145
Checking a particular Slk?
See its own MOT history, advisories and mileage for free.
Slk MOT pass rate by year
Older cars fail more often, so each year is compared with all cars of the same age. Bars above the dashed line did better than average for their age.
| First registered | Tests | Pass rate | All cars, same age | Difference | Avg mileage |
|---|---|---|---|---|---|
| 2016 | 1,265 | 87% | 79% | +8.3 points | 37,741 |
| 2015 | 4,858 | 83% | 75% | +7.4 points | 43,449 |
| 2014 | 4,916 | 80% | 72% | +8.7 points | 50,466 |
| 2013 | 4,641 | 77% | 68% | +8.6 points | 57,982 |
| 2012 | 5,580 | 77% | 66% | +11.4 points | 59,681 |
| 2011 | 2,551 | 77% | 63% | +14.4 points | 56,853 |
| 2010 | 2,097 | 71% | 60% | +10.7 points | 62,950 |
| 2009 | 2,515 | 68% | 59% | +8.7 points | 66,161 |
| 2008 | 3,265 | 69% | 57% | +11.4 points | 72,067 |
| 2007 | 3,564 | 68% | 57% | +11.5 points | 73,195 |
| 2006 | 3,831 | 68% | 56% | +12.2 points | 77,212 |
| 2005 | 5,012 | 67% | 56% | +10.6 points | 80,272 |
| 2004 | 3,230 | 65% | 56% | +9.4 points | 82,161 |
| 2003 | 1,894 | 65% | 57% | +8.5 points | 83,522 |
| 2002 | 2,078 | 70% | 58% | +12.8 points | 85,870 |
| 2001 | 2,378 | 69% | 59% | +10.4 points | 88,973 |
| 2000 | 2,049 | 69% | 61% | +8.4 points | 90,000 |
| 1999 | 1,613 | 68% | 62% | +5.5 points | 86,870 |
| 1998 | 1,164 | 69% | 64% | +5.4 points | 89,149 |
| 1997 | 794 | 68% | 64% | +3.5 points | 89,178 |
Why the Mercedes-Benz Slk fails its MOT
The share of tests with at least one failure in each area, compared with all cars.
| Failure area | Slk | All cars |
|---|---|---|
| Suspension | 11.0% | 8.9% |
| Lights and electrics | 8.6% | 11.3% |
| Tyres | 6.3% | 6.3% |
| Brakes | 6.0% | 6.8% |
| Visibility | 3.3% | 4.8% |
| Noise, emissions and leaks | 2.5% | 3.1% |
| Body and structure | 1.5% | 3.5% |
| Seatbelts and airbags | 1.2% | 1.0% |
| Steering | 0.8% | 1.8% |
| Road Wheels | 0.4% | 0.4% |
Top 10 specific failure reasons
- 1fractured or broken5.1%
- 2not working3.9%
- 3ball joint excessively worn2.6%
- 4tread depth below requirements of 1.6mm2.3%
- 5has ply or cords exposed1.7%
- 6excessively corroded1.7%
- 7inoperative or indicates a malfunction1.6%
- 8ball joint dust cover no longer prevents the ingress of dirt1.6%
- 9does not clear the windscreen effectively1.2%
- 10has a cut in excess of the requirements deep enough to reach the ply or cords1.2%
Common Slk MOT advisories
Advisories don't cause a fail, but they show what's wearing out. On a used Slk, check whether these have been dealt with. Read our guide to MOT advisories.
| Advisory | Area | Share of tests |
|---|---|---|
| tread depth below requirements of 1.6mm | Tyres | 14.4% |
| excessively corroded | Brakes | 11.1% |
| has a tear, caused by separation or partial failure of its structure | Tyres | 7.7% |
| in such a condition that it is seriously weakened | Brakes | 7.4% |
| less than 1.5 mm thick | Brakes | 5.1% |
| has excessive play | Suspension | 4.5% |
| pin or bush excessively worn | Suspension | 4.1% |
| corroded and seriously weakened | Suspension | 3.5% |
| leaking excessively from engine | Noise, emissions and leaks | 3.1% |
| ball joint excessively worn | Suspension | 2.9% |
Tips to help your Slk pass
Based on where Slks most often fail. For a full list, use our pre-MOT checklist.
Lights and electrics · 8.6% of Slk tests
Walk round every light
With a helper, check headlights on dipped and main beam, sidelights, brake lights, indicators, the rear fog light and the number plate lamp. Replace blown bulbs in pairs and make sure no lenses are cracked.
Brakes · 6.0% of Slk tests
Don't ignore brake warning signs
Grinding, squealing, a soft pedal or the car pulling to one side under braking are all worth investigating before the MOT. Check whether the last test noted worn pads or discs; if so, they may now be below the limit.
Compare with other models
Is the Slk ULEZ compliant? See the Mercedes-Benz Slk ULEZ check, or view all Mercedes-Benz models.
Other Mercedes-Benz models
Models with similar pass rates
About this data
Based on 59,347 first MOT tests of the Mercedes-Benz Slk carried out in 2023.
Source: DVSA anonymised MOT test data (contains public sector information licensed under the Open Government Licence v3.0). First attempts on cars only; “pass rate” means passing first time. Averages cover all 32,735,164 cars tested (71% passed), and years with under 50 tests are hidden.
Learn more about how our data works.
Frequently asked questions
Answers from 59,347 first MOT tests of the Mercedes-Benz Slk.
What is the Mercedes-Benz Slk MOT failure rate?
In our data, 27% of 59,347 first MOT attempts on the Mercedes-Benz Slk ended in a fail, compared with 29% for all cars.
What is the most common reason a Mercedes-Benz Slk fails its MOT?
The most common failure areas were suspension (11.0% of tests), lights and electrics (8.6% of tests), tyres (6.3% of tests).
Which Slk year has the best MOT pass rate?
Allowing for age, 2011 cars performed best: 77% passed first time, +14.4 points against the average for 12-year-old cars. The weakest was 1997, at 68% (+3.5 points).
How many miles had a typical Mercedes-Benz Slk covered at its MOT?
The average was 68,471 miles, against 73,145 for all cars tested. 2016 cars averaged 37,741 miles and 1997 cars 89,178.
What is the most common MOT advisory on the Mercedes-Benz Slk?
"tread depth below requirements of 1.6mm" was recorded on 14.4% of tests, in the tyres area. 6.3% of Slks failed in that area too.
How can I check a specific Slk's MOT history?
Enter its registration in our free MOT check. Across the 59,347 Slks in our data, first-time pass rates ranged from 65% to 87% by year, so one car's own record says more than the average.
Related guides
- MOT · 6 min readThe most common reasons cars fail their MOT (and how to avoid them)Lights alone failed 11.3% of cars at their 2023 MOT, more than any other area. The common failure areas, ranked, and the driveway checks that prevent them.Read the guide
- MOT · 6 min readPre-MOT checklist: 20 things to check yourself before the testTwenty quick checks, grouped by area, that you can do on your driveway in under half an hour. No tools beyond a coin and a helper needed for most.Read the guide
- MOT · 4 min readTyre tread depth and the MOT: the legal limit and how to check6.3% of cars failed their 2023 MOT on tyres. The 1.6mm legal limit, what testers look for beyond tread, and a one-minute check with a 20p coin.Read the guide
Check any Slk's MOT history
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