Mercedes-Benz C-Class MOT pass rate and common problems

Mercedes-Benz C-Class common problems: what should I check before buying?

The faults recorded most often at Mercedes-Benz C-Class MOTs in 2019–2024, per 100 tests.

• Worn suspension bush or joint6.00
  Major

  What to check: Listen for knocks over speed bumps, feel for the car wandering under braking, and ask which part was replaced.

• Tyre tread below the legal limit4.84
  Dangerous

  What to check: Check the tread across every tyre with a gauge; wear on one edge points to a tracking fault.

• Suspension joint cover perished3.55
  Minor

  What to check: Look at the ball joint covers behind the front wheels: once a cover splits, the joint wears out.

• Tyre badly cut or damaged2.87
  Major

  What to check: Check both sidewalls of every tyre, including the inner side, for cuts, bulges and tears.

• Windscreen or window damaged2.79
  Minor

  What to check: Look for chips and cracks across the windscreen: chips spread, and larger damage in front of the driver fails.

One test can record several defects, so this is not the share of Mercedes-Benz C-Class models.

Each tip applies only if the car you are looking at has that fault in its own MOT history.

Which Mercedes-Benz C-Class years should I avoid?

2004 is the Mercedes-Benz C-Class year that fails its MOT most for its age; 1998 fails least.

Fails more for its age: 2003, 2004, 2005, 2012, 2013.

Fails less for its age: 1998, 1999, 2000, 2019.

Year means the year the car was first registered, as DVSA records it. It may differ from the year it was built.

How does the Mercedes-Benz C-Class compare with similar cars?

6 of 8 similar models fail less often for their age than the Mercedes-Benz C-Class.

This is a different comparison from the one at the top. There, the Mercedes-Benz C-Class is measured against all cars of the same age. Here, it sits among similar models. Both can be true.

How do Mercedes-Benz C-Class models hold up as they get older?

First-time MOT failures on Mercedes-Benz C-Class models go from 12.4% at age 3 to 42.2% at age 19.

Download every age and sample size (CSV)

Do advisories on Mercedes-Benz C-Class models turn into fails at the next MOT?

25.3% of lights and electrical advisories on Mercedes-Benz C-Class models turned into lights and electrical fails at the next MOT.

The next MOT came about 12 months later.

Based on 15,098 advisories, each followed to the car's next MOT, 2019–2024. This counts advisories, not cars.

The most common advisories on Mercedes-Benz C-Class models are for tyres: 40.94 per 100 tests.

Download all advisory transitions (CSV)

Mercedes-Benz C-Class common problems: what actually fails the MOT?

Mercedes-Benz C-Class MOTs fail most often on suspension: 16.4 per 100 tests, against 13.8 for UK cars of the same age (2019–2024, n = 2,072,470).

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What is likely to fail next on a used Mercedes-Benz C-Class?

For Mercedes-Benz C-Class models aged 3 to 5 whose last MOT was a pass, the item most likely to fail at the next MOT is tyres: 5.9% failed on it (2019–2024, n = 281,511).

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How often do Mercedes-Benz C-Class models get a dangerous MOT defect?

The Mercedes-Benz C-Class gets a dangerous defect about as often as the UK average: 11.7 per 100 first tests against 11.2 across the UK. In the same tests, 38.0 major and 11.0 minor defects were recorded per 100 tests (one test can record several).

Severity was not recorded for some 2018–2021 tests.

Comparison: 11.2 per 100.

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How much do Mercedes-Benz C-Class MOT repairs cost?

Expected repair cost per Mercedes-Benz C-Class MOT: about £74 (up to about £141 if more expensive parts are needed), from the chance of failing each item and its most common UK repair price (catalogue estimate, n = 365,590).

Computed, not measured.

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What mileage is normal for a used Mercedes-Benz C-Class?

At age 8, the median Mercedes-Benz C-Class had covered 69,646 miles by its MOT; the middle half ranged from 52,091 to 90,979 miles (2024, n = 37,146).

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Do high-mileage Mercedes-Benz C-Class models fail their MOT more often?

At ages 6–9, 11.9% of Mercedes-Benz C-Class models with under 40,000 miles failed first time, against 23.1% of those with over 140,000 miles (2024, n = 30,479). Inside this age group, higher mileage goes with more failures.

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How many miles do Mercedes-Benz C-Class models last?

27.6% of Mercedes-Benz C-Class models tested had reached 100,000 miles, and 6.7% had reached 150,000 (2024, n = 567,856).

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Does mileage, as well as age, change the Mercedes-Benz C-Class failure index?

Matched on annual mileage as well as age, the Mercedes-Benz C-Class index is 82.3, against 86.2 on age alone (2019–2024, n = 365,590).

Comparison: 86.2 index.

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Which Mercedes-Benz C-Class fuel type fails its MOT less?

There is no real difference between diesel and petrol Mercedes-Benz C-Class models before allowing for age: 27.1% against 25.4% fail first time.

Comparison: other fuels.

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Which Mercedes-Benz C-Class engine fails its MOT least?

Among engines with enough tests, the best Mercedes-Benz C-Class engine is the petrol 1.2–1.5 litre at index 78.3, and the worst the diesel 1.5–1.8 litre at 111.2, where 100 = the model's own average (2024, n = 365,590).

Comparison: 100 = model average.

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Where in Britain does the Mercedes-Benz C-Class fail its MOT most?

Mercedes-Benz C-Class fails first-time MOTs most in Kirkcaldy (KY): 37.0% against 24.5% across Britain for this model, both 2019–2024 (2019–2024, n = 5,722).

Across Britain for this model: 24.5% failed first time, also in 2019–2024.

See every postcode area and its sample size

Does the Mercedes-Benz C-Class have rust problems?

Allowing for age, Mercedes-Benz C-Class MOTs record corrosion failures at 2.3 times the national rate: 1.79% of tests against 0.77% (2024 + geographic layers, n = 362,129).

Computed, not measured.

Comparison: 1 ratio estimate.

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What do six years of MOTs show about owning a used Mercedes-Benz C-Class?

Of failed Mercedes-Benz C-Class MOTs, 39.0% were retested the same day and a further 57.5% within 10 days; the median failed car passed its retest after 1 day (2019–2024, n = 375,754).

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Is low mileage good for a used Mercedes-Benz C-Class?

Mercedes-Benz C-Class models aged 5 to 14 doing under 5,000 miles a year failed first time in 14.8% of tests, against 26.2% for those doing 8,000 to 12,000 miles (2019–2024, n = 161,959).

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How many years do Mercedes-Benz C-Class models last?

Mercedes-Benz C-Class models leave the road sooner than most: at ten years old the typical one has about 5.4 more years of MOTs ahead. This is a forecast from the survival curve and may not come true.

Computed, not measured.

Forecast, not a prediction for a particular car.

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How many Mercedes-Benz C-Class models are still on the road as they age?

In 2024, for every 100 Mercedes-Benz C-Class models tested at ages 4 to 6, about 17 were tested at age 19 (2024, n = 31,362).

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If a used Mercedes-Benz C-Class fails its MOT, will it fail the next one?

30.2% of Mercedes-Benz C-Class models that failed an MOT failed the next one too, against 21% after a pass (2019–2024, n = 97,574). The failure most likely to come back is ‘lamps, reflectors and electrical equipment’: 33.1% of those fails recurred at the next MOT.

Comparison: 21 %.

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Which Mercedes-Benz C-Class faults tend to come together?

On Mercedes-Benz C-Class models, ‘lamps, reflectors and electrical equipment’ and speedometer and speed limiter failures turn up together 8.6 times as often as chance would predict (2024, n = 23).

Comparison: expected joint rate.

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Mercedes-Benz C-Class safety recalls: how do I check this car?

DVSA lists 158 safety recall campaigns matched to the Mercedes-Benz C-Class; check whether yours has been fixed, using its registration number.

Comparison: DVSA register.

Check outstanding safety recalls by registration

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How many Mercedes-Benz C-Class models fail the MOT at each age?

Of every 100 Mercedes-Benz C-Class models tested at age 5, about 13 failed the MOT first time; at age 10, about 24. These are one-year rates for different cars tested in the same year, not a fleet followed over time; the steepest one-year step in this cross-section is between cars aged 10 and 11, 6.51 percentage points (2024).

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What have US dealers been told about the Mercedes-Benz C-Class?

NHTSA lists 777 US technical service bulletins for the Mercedes-Benz C-Class (US market, Mercedes-Benz C-CLASS, model years 2015–2022 only); a count, not a UK failure rate.

Comparison: NHTSA.

NHTSA, US market, Mercedes-Benz C-CLASS, model years 2015–2022 only; covers 211 of 761 models. These two sections use US records from NHTSA. US cars sold under the same name can differ from UK ones.

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What do US owners complain about on the Mercedes-Benz C-Class?

The most common US owner complaint about the Mercedes-Benz C-Class to NHTSA concerns engine (not MOT-tested): 396 complaints (US market, Mercedes-Benz C-CLASS, model years 2015–2022 only).

NHTSA, US market, Mercedes-Benz C-CLASS, model years 2015–2022 only; covers 211 of 761 models. These two sections use US records from NHTSA. US cars sold under the same name can differ from UK ones.

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Do Mercedes-Benz C-Class models fail their MOT more in some months?

Mercedes-Benz C-Class models fail first time most in November (25.9%, against 30.6% for all cars that month) and least in June (23.5%) (2024, n = 365,590).

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How far is real-world MPG from the lab figure for Mercedes-Benz cars?

Real-world fuel use of 2021 diesel cars from Mercedes-benz AG is 16.2% above the official WLTP figure: 7.16 against 6.16 litres per 100 km (2021+ cohorts, n = 137,711 vehicles).

Computed, not measured.

Plug-in hybrids: the lab figure assumes the battery is charged often; on the road many are driven mostly on petrol, so the gap is several times larger.

Comparison: 0% gap.

European Commission OBFCM; covers 19 of 761 models.

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More on the Mercedes-Benz C-Class

Overview:

Model overview · All Mercedes-Benz models

Build years:

1998 · 1999 · 2000 · 2001 · 2002 · 2003 · 2004 · 2005 · 2006 · 2007 · 2008 · 2009 · 2010 · 2011 · 2012 · 2013 · 2014 · 2015 · 2016 · 2017 · 2018 · 2019 · 2020

What fails:

body · brakes · plates · lights · emissions · wheels · seat belts · steering · suspension · tyres · visibility

Abroad:

Finland · the Netherlands · Norway

By area:

Postcode areas

Compare:

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