2025 MOT results
Mercedes-Benz CLK-Class common problems
The most common reason a Mercedes-Benz CLK-Class fails its MOT is a worn steering or suspension joint, on 17.6% of its 9,231 failed tests in 2025. Against other cars of the same age, 4 faults stand out, the widest gaps being: a worn steering or suspension joint at 17.6% of failures against 5.4% expected; a broken coil spring at 16.5% of failures against 7.4% expected; the airbag light on at 6.1% of failures against 2.8% expected.
- Tests in 2025 25,047 Cars aged three and over
- Failed first time 36.9% 9,231 tests
- Found a dangerous defect 9.3% Unsafe to drive away
- Ended with an advisory 66.5% A problem to watch, not a failure
What fails a Mercedes-Benz CLK-Class MOT
Each bar is the share of failed Mercedes-Benz CLK-Class tests with that defect. Where we can compare it with cars of the same registration years, the marker shows what an average car of those ages records (12 of the 12 items below).
Most common reasons for failure
A test can fail for more than one defect, so shares add up to more than 100%.
| Defect | Share of failed tests |
|---|---|
| Suspension arms: ball joint excessively worn Suspension | 17.6% |
| Coil spring: fractured or broken Suspension | 16.5% |
| Headlamp aim: projected beam image is obviously incorrect Lamps, reflectors and electrical equipment | 9.5% |
| Malfunction indicator lamp: inoperative or indicates a malfunction Noise, emissions and leaks | 7.8% |
| Tyres: tread depth below requirements of 1.6mm Tyres | 6.9% |
| Position lamp: not working Lamps, reflectors and electrical equipment | 6.6% |
| Linkage ball joint dust cover no longer prevents the ingress of dirt Suspension | 6.2% |
| SRS malfunction indicator lamp: warning lamp indicates a fault Seat belts and supplementary restraint systems | 6.1% |
| Parking brake efficiency below requirements Brakes | 5.8% |
| Suspension arms: pin or bush excessively worn Suspension | 5.7% |
| Wipers: does not clear the windscreen effectively Visibility | 5.7% |
| Track rod end: ball joint has excessive play Steering | 5.4% |
Source:DVSA,UK Motoring analysis 2025 Updated
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Worn steering or suspension joint
17.6% of failures 5.4% expected 3.3 times as often
Play in a steering or suspension joint, where a worn ball and socket lets the wheel move where it should not.
A knock at low speed over rough ground, or vague steering, is the usual warning.
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Broken coil spring
16.5% of failures 7.4% expected 2.2 times as often
A broken suspension spring, which usually snaps in the bottom coil and often fails on both sides within a year.
Look at each corner for a sagging ride height, and listen for a knock over speed bumps.
-
Headlamp aim out of line
9.5% of failures 8.8% expected about as expected
The beam pattern points too high, too low, or in the wrong place, so it either dazzles others or lights too little road.
Nothing to do at the roadside, but a garage resets the aim in minutes; a sagging suspension corner or a heavy boot load can throw it out.
-
Engine management light on
7.8% of failures 6.4% expected somewhat more often
The engine management light is on, or has been disconnected. Either fails the test.
A cheap code reader on the diagnostic socket will say what the car has stored before you pay for a test.
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Tyre worn below the legal limit
6.9% of failures 6.1% expected about as expected
A tyre worn past the 1.6mm legal minimum across the middle three quarters of the tread.
A 20p coin in the main grooves: if the outer band of the coin is visible, the tyre is close to the limit.
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Sidelight out
6.6% of failures 12.9% expected 2 times less often
A sidelight, also called a position lamp, not working. It marks the width of the car at night.
Walk round the car with the lights on and the hazards going; these are the cheapest failures to avoid.
Which parts of the car fail
Suspension is the area that most often fails a Mercedes-Benz CLK-Class, on 49.4% of failed tests. That is also where it differs most from cars of the same registration years, which record 39.5%.
Failure categories
DVSA's own sections of the test. The marker is what cars of the same registration years record.
| Defect category | Share of failed tests |
|---|---|
| Suspension | 49.4% |
| Lamps, reflectors and electrical equipment | 37.6% |
| Brakes | 26.5% |
| Tyres | 19.9% |
| Visibility | 15.3% |
| Noise, emissions and leaks | 13.6% |
| Steering | 8.2% |
| Body, chassis, structure | 7.2% |
Source:DVSA,UK Motoring analysis 2025 Updated
What testers warn about
66.5% of Mercedes-Benz CLK-Class tests ended with at least one advisory: a fault the tester found that did not fail the test. On Mercedes-Benz CLK-Classes, these are the items to ask about on a car you are viewing, because they are what the last tester expected to go next.
Most common advisories
Share of all tests, passes included.
| Advisory | Share of tests |
|---|---|
| Rigid brake pipes: corroded, covered in grease or other material Brakes | 20.0% |
| Tread depth: worn close to legal limit or worn on edge Tyres | 18.6% |
| Brake discs: worn, pitted or scored, but not seriously weakened Brakes | 9.6% |
| Engine oil leak, but not excessive Noise, emissions and leaks | 9.3% |
| Suspension arms: pin or bush worn but not resulting in excessive movement Suspension | 7.8% |
| Tyres: slightly damaged or cracking or perishing Tyres | 7.7% |
| Wheel bearings: slight play Suspension | 7.1% |
| Sub-frame: corroded but not seriously weakened Suspension | 7.1% |
| Brake pads: wearing thin Brakes | 6.9% |
| Suspension arms: ball joint has slight play Suspension | 6.7% |
| Coil spring: corroded Suspension | 6.5% |
| Flexible brake hoses: slightly deteriorated Brakes | 5.8% |
Source:DVSA,UK Motoring analysis 2025 Updated
What changes as a Mercedes-Benz CLK-Class gets older
A 2009 Mercedes-Benz CLK-Class failed 39.4% of its MOT tests in 2025; a 2003 one failed 34.2%. What fails changes as much as how often, and these are the two years themselves rather than an average across them.
2009 Mercedes-Benz CLK-Class 39.4% failed, from 2,748 tests
- Worn steering or suspension joint 21.6%
- Broken coil spring 20.2%
- Tyre worn below the legal limit 8.9%
- Split joint boot 7.5%
- Worn suspension bushes 7.5%
- Weak handbrake 6.5%
2003 Mercedes-Benz CLK-Class 34.2% failed, from 2,427 tests
- Broken coil spring 15.7%
- Worn steering or suspension joint 13.1%
- Headlamp aim out of line 12.1%
- Airbag light on 10.4%
- Worn suspension bushes 8.3%
- Wiper blades that do not clear the screen 7.7%
Shares are of each year's failed tests. Every MOT a particular car has had, with the defects and advisories written at each test, is on GOV.UK's MOT history service from the registration, free.
Mercedes-Benz CLK-Class problems: common questions
What is the most common problem with a Mercedes-Benz CLK-Class?
Of the faults that fail an MOT, “Suspension arms: ball joint excessively worn” is the most common: it appears on 17.6% of failed Mercedes-Benz CLK-Class tests. Across categories, suspension is the area that most often fails one, on 49.4% of failed tests.
How often does a Mercedes-Benz CLK-Class fail its MOT?
36.9% of Mercedes-Benz CLK-Class tests in 2025 were not passed first time, from 25,047 tests of cars aged three and over. Allowing for the age and mileage of the cars tested, that gives it a UK Motoring Reliability Score of 53 out of 100, where 50 is as expected.
Does anything fail more often on a Mercedes-Benz CLK-Class than on other cars?
Yes. “Suspension arms: ball joint excessively worn” appears on 17.6% of its failures against 5.4% for cars of the same age, and “Coil spring: fractured or broken” appears on 16.5% of its failures against 7.4% for cars of the same age. Where an item is missing from the national figures for a year, we use the smallest share those figures show, so the comparison never overstates the difference.
Are these the same as breakdowns or known faults?
No. These are the items a tester recorded at the MOT, which covers condition and safety: lamps, brakes, tyres, suspension, corrosion and emissions. A gearbox that is unpleasant, an infotainment screen that has died, or a car that will not start on a cold morning are not part of the test, so they are not in these figures.
Where do the figures come from?
Every normal MOT test of a Mercedes-Benz CLK-Class aged three and over in Great Britain in 2025, from DVSA's anonymised MOT results. Retests are excluded, and the same fault on more than one wheel counts once.
Data stories to read next
Data sources and methodology
| Figures | Source | Period | Records | Updated |
|---|---|---|---|---|
| MOT defects and advisories | Anonymised MOT tests and results Driver and Vehicle Standards Agency Derived statistics UK Motoring | 2025 | 25,047 MOT tests | 19 September 2026 |
- Shares for defects are of failed tests; shares for advisories are of all tests. A test can carry several defects, so shares add to more than 100%.
- The expected share is what an average car of the same registration years records, weighted by where this model’s failures fall. Where an item is outside the national figures for a year, the smallest share those figures show is used in its place, which is an upper bound, so the comparison never overstates a model’s problems. No expectation is published where less than 80% of the model’s failures can be compared.
- Great Britain only: DVSA does not run MOT testing in Northern Ireland. Cars under three years old are not tested.
- The descriptions of what each part does are general and the same on every model. Every figure comes from the MOT data.
Contains public sector information licensed under the Open Government Licence v3.0.