2018 · 6 years old at test · Diesel mostly

2018 Mercedes-Benz C-Class MOT pass rate and common faults

28,019 MOT tests in 2024. 84.8% passed first time, compared with 82.5% for all cars the same age.

103Above average
Passed first time84.8%
Failed or needed repairs15.2%
Typical mileage at test48,000

Most common reasons for failing

Share of all 28,019 tests where this item caused a failure.

  1. Tread depth below requirements of 1.6mm3.0%
    1,453 marked dangerous
  2. Tyres - condition: has ply or cords exposed1.8%
    796 marked dangerous
  3. Tyres - condition: has a cut in excess of the requirements deep enough to reach the ply or cords1.8%
  4. Malfunction indicator lamp: inoperative or indicates a malfunction1.4%
  5. Suspension arms - ball joint: ball joint excessively worn1.2%
  6. Coil spring: fractured or broken1.1%
  7. Brake pads: less than 1.5 mm thick0.9%
    344 marked dangerous
  8. Tyres - condition: has a bulge, caused by separation or partial failure of its structure0.9%
    341 marked dangerous
  9. Road Wheels - condition: fractured0.5%
    261 marked dangerous
  10. Headlamp aim: too low0.5%

Problem areas

Failure items found per 100 tests, by part of the car.

  1. Tyres8.9%
  2. Suspension2.7%
  3. Brakes2.1%
  4. Emissions & leaks2.0%
  5. Lights & electrics1.8%
  6. Visibility (wipers, screen, mirrors)1.5%
  7. Wheels0.8%
  8. Number plates & VIN0.3%

Most common advisories

Not failures yet, but things the tester warned about.

  1. Tread depth below requirements of 1.6mm18.4%
  2. Brake pads: less than 1.5 mm thick7.9%
  3. Brake discs: in such a condition that it is seriously weakened5.1%
  4. Tyres - condition: has a tear, caused by separation or partial failure of its structure4.4%
  5. Suspension arms - ball joint: ball joint excessively worn3.3%

What this means if you are buying one

This model year does better than most cars its age, so it is a reasonable used buy on MOT record alone. Before buying, check the area that fails most: tread depth below requirements of 1.6mm. Then look up the car's own MOT history on GOV.UK with its number plate, and look for repeat advisories.

← 2017 C-ClassAll C-Class years2019 C-Class →

Questions

What is the MOT pass rate for a 2018 Mercedes-Benz C-Class?

In 2024, 84.8% of 2018 Mercedes-Benz C-Class cars passed their MOT first time, across 28,019 tests. The average for all 6-year-old cars was 82.5%.

What are the most common MOT failures on a 2018 Mercedes-Benz C-Class?

The most common failure reasons were tread depth below requirements of 1.6mm; tyres - condition: has ply or cords exposed; tyres - condition: has a cut in excess of the requirements deep enough to reach the ply or cords. The biggest problem area was tyres.

Is the 2018 Mercedes-Benz C-Class reliable at MOT time?

Its MOT Rank score is 103, which is above average for a car of its age (100 means exactly average).