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What to check: Mercedes CLC

Ranked across all years of the Mercedes CLC, from its own MOT record and from what owners report. Tick it off at the car.

From this model's MOT record

The physical checks its own defect data says are worth your time, most telling first.

Brake pipes underneathRuns high on this modelFollow the metal brake lines with a torch where they run along the sills and over the rear axle. White crust or flaking metal means they are corroding, and the online MOT history usually shows the same advisory creeping up for years before the fail.Recorded on 25.3% of tests at age 10-15 · class average 6.2%

Bushes and ball jointsRuns high on this modelDrive slowly over broken tarmac with the windows down and listen for clonks from either end. Back at the car, have someone rock the steering wheel while you rest a hand on each front wheel; play you can feel through the tyre is a worn joint.Recorded on 14.2% of tests at age 10-15 · class average 9.0%

Wheel bearingsRuns high on this modelOn the test drive, listen for a drone that rises with road speed and shifts when you sway the car gently between lanes. That is a wheel bearing, and it only ever gets louder.Recorded on 9.5% of tests at age 10-15 · class average 0.6%

Coil springsRuns high on this modelLook through the wheel spokes at the bottom coil of each spring; when springs snap it is usually there, and the break is visible. Step back and check the car sits level too. A dropped corner is often a broken spring.Recorded on 8.9% of tests at age 10-15 · class average 3.2%

Steering playRuns high on this modelWith the engine running and the car parked, waggle the wheel lightly about the straight-ahead. The wheels should respond almost at once. A dead zone before anything happens means wear in the rack or the track rod ends.Recorded on 6.1% of tests at age 10-15 · class average 1.7%

ExhaustRuns high on this modelListen along the exhaust at cold idle for blowing or chuffing, and give the tailpipe a push to check nothing hangs loose. Small blows only get louder.Recorded on 5.7% of tests at age 10-15 · class average 0.9%

Headlamp lensesRuns high on this modelCheck for condensation inside the headlamps and for cloudy or yellowed lenses. Both attract MOT trouble, and moisture inside a sealed LED unit generally means a whole new lamp.Recorded on 5.4% of tests at age 10-15 · class average 1.1%

Worth doing on any used car

These judge the seller's upkeep rather than the model.

Tyres, all fourCheck the tread across the full width of each tyre, inner edge included, and look for cracking and mismatched brands. A set of decent tyres is £500 or more on most cars, which makes this the easiest money to take off a price. If the pressure warning light is on, budget for sensors too.Recorded on 26.5% of tests at age 10-15 · class average 20.9%

Pads and discsLook through the wheel spokes at the brake disc. A pronounced lip on its outer edge, or a rusty and scored face, means discs and pads are due all round, a few hundred pounds on most cars. A haggling point rather than a reason to walk away.Recorded on 12.6% of tests at age 10-15 · class average 11.4%

Windscreen and wipersScan the glass in daylight for chips, especially in the driver's line of sight where even a small one can fail the MOT. Run the washers and check the wipers clear without smearing.Recorded on 3.5% of tests at age 10-15 · class average 2.6%

Because of what owners report

Drawn from the owner reports rather than the MOT data. These are the model-specific ones.

Start the engine from cold and listen for 30 seconds before revving it.A rattly, chainsaw-like noise from the front of the engine points to M271 timing chain tensioner wear.

On an automatic, drive it through every gear including a full-throttle kickdown.Hesitant, harsh or delayed shifts, or a gearbox warning light, suggest the 722.6 conductor plate is on its way out.

Get down and check the rear wheel arches, sills and exhaust hangers for bubbling paint or filler.Rust here is expensive to fix properly and can fail an MOT once it reaches structural areas.

On a diesel, watch the exhaust and listen to the idle on a cold start.Heavy smoke or a rough idle before it warms up points to tired glow plugs or a swirl flap problem.

Operate the indicators, wipers and central locking together and watch for random warning lights.Intermittent faults across unrelated electrical systems usually trace back to a failing SAM module.

Check the front discs for scoring or a lip, and brake hard from low speed.Pulling to one side, grinding or a spongy pedal points to worn discs, pads or a sticking caliper, the fault behind this model's MOT brake failures.

Read through the MOT history for repeated brake advisories.The same brake advisory coming back year after year confirms how often this shows up in the test data for this model.

Full Mercedes CLC reliability report