Used Mercedes-Benz CLK buying guide

In 2025, Mercedes-Benz CLK cars passed 63.1% of 25,046 initial MOT tests, 9.2 points below the 72.3% UK average. Here is where it fails and what to check before you buy.

Looking at a specific CLK? Check its finance, write-off, stolen, mileage and keeper history. £15, no account needed.

Mercedes-Benz CLK MOT record in brief

Initial MOT tests in 2025, retests excluded.

63.1%

Mercedes-Benz CLK pass rate

72.3%

UK average, all cars

−9.2

percentage points below average

Ranked on pass rate the CLK sits 457th of 575 models in the data. Mercedes-Benz as a brand averaged 77.1%, so this model runs 13.9 points behind its own brand.

A pass rate is not a reliability score. The full Mercedes-Benz CLK MOT record has the pass rate by age, every common failure and how the CLK compares with similar cars.

CLK fuel types

Petrol was the most common fuel among Mercedes-Benz CLK cars tested in 2025. Diesel still made up 18.5% of tests.

Where the CLK fails its MOT

Where Mercedes-Benz CLK cars that failed their 2025 MOT were marked down, as a share of all recorded failure items.

  • Suspension28.7%
  • Lamps, reflectors and electrical equipment22.3%
  • Brakes16.1%
  • Tyres9.5%
  • Noise, emissions and leaks6.2%
  • Visibility6%

The specific items testers recorded most often were ball joint excessively worn (7.9%), coil spring fractured or broken (6.6%) and headlamp aim projected beam image is obviously incorrect (4.9%). See every common CLK MOT failure.

These are DVSA failure records across every Mercedes-Benz CLK that failed, not a claim that every CLK has these problems.

What should you check when buying a used CLK?

The areas above, most common first, and what an MOT tester looks at in each.

1

Suspension

Listen for knocks over bumps, check the car sits level, and look for leaking shock absorbers and split rubber gaiters. 28.7% of CLK failure items.

2

Lamps, reflectors and electrical equipment

Walk round with every light on: headlights, brake lights, indicators, fog lights and the number plate lamp. Check no warning lights stay on after starting. 22.3% of CLK failure items.

3

Brakes

Make sure the pedal feels firm, the car stops in a straight line, the handbrake holds on a slope and no brake warning light is showing. 16.1% of CLK failure items.

4

Tyres

Check tread depth across the full width of every tyre (the legal minimum is 1.6mm), and look for cuts, bulges and uneven wear. 9.5% of CLK failure items.

5

Noise, emissions and leaks

Listen for a blowing exhaust, watch for smoke on start-up and look under the car for oil or fluid leaks. 6.2% of CLK failure items.

None of this replaces the car's own record. Run a free MOT history check on the registration to see every test, advisory and recorded mileage for that car.

What the MOT record doesn't tell you

Knowing Mercedes-Benz CLK failures cluster around suspension and lamps, reflectors and electrical equipment tells you what to inspect. It tells you nothing about whether the car is safe to buy. An MOT does not show money still owed on the car, a write-off, a theft record or a clocked odometer.

Check the exact CLK you are looking at. One £15 report, instant results, backed by a £30,000 data guarantee. More on the Mercedes-Benz history check.

  • Outstanding finance
  • Write-off records
  • Stolen markers
  • Mileage history
  • Previous keepers

Used Mercedes-Benz CLK FAQs

Is the Mercedes-Benz CLK reliable?

MOT data does not measure reliability. It records whether a car met the roadworthiness standard on the day of its test. What it does show is a 63.1% first-time pass rate for the Mercedes-Benz CLK across 25,046 tests in 2025, below the 72.3% average for all cars.

What should I check before buying a used Mercedes-Benz CLK?

On the car itself, start with the areas it most often fails on: suspension, lamps, reflectors and electrical equipment and brakes. Then check the individual car's history: outstanding finance, insurance write-off records, stolen markers, mileage and previous keepers. None of these appear in the MOT record or on the V5C.

How do I check a Mercedes-Benz CLK's history?

Enter the registration of the specific car. A Carpeep car history check reports outstanding finance, write-off category, stolen markers, mileage history, previous keepers, MOT and tax status, import and export markers and scrapped status in one £15 report.

MOT figures are aggregated from the DVSA MOT Anonymised data set for 2025 (class 4 initial tests, retests excluded), licensed under the Open Government Licence v3.0. MOT results describe roadworthiness at test, not mechanical reliability.