Used car guide

2023 Mercedes-Benz C-Class diesel: common problems and MOT failures

What MOT testers find on the diesel Mercedes-Benz C-Class first registered in 2023 (diesel cars only): we looked at the 144 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.

Small sample: there were only 144 MOTs of these cars during 2023–2025, so treat the percentages as rough. The known faults below don't depend on it.

144MOTs of 2023 diesel cars, done in 2023–2025
94%pass first time (all 2023 cars: 92%)
7,600typical miles a year
16%had tyres flagged

Common 2023 Mercedes-Benz C-Class diesel MOT failures and advisories

The share of 2023 Mercedes-Benz C-Class diesel MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    16% of testsRough price £70–£150

    At the viewing: Check the tread on all four tyres, including the inside edges, and look for cracks or bulges.

  • Wipers, windscreen and mirrors
    3% of testsRough price £15–£250

    At the viewing: Check for chips in the driver's view, and test the wipers and washers.

  • Brakes
    1% of testsRough price £150–£350

    At the viewing: Look for a lip on the disc edges and feel for judder or pulling when braking firmly from about 40mph.

  • Lights and electrics
    1% of testsRough price £10–£80

    At the viewing: Ask a friend to check every light, including brake lights and indicators, while you operate them.

Known faults on the 2023 Mercedes-Benz C-Class diesel

Reported by owners, mechanics and buying guides for this model and age. Check which engine the car has, as some apply to one engine only.

  • Fuel pump recall

    All engines

    Some 2022-23 cars were recalled because the fuel pump impeller can deform.

    At the viewing: Run the free DVSA recall check on the reg.

    Source: What Car?: Mercedes C-Class (2021 on) reliability

  • Poor reliability record

    All engines

    In What Car?'s survey, 43% of these C-Classes had a fault, with problems in the air con, engine, fuel system, gearbox and electrics. Many left the car undriveable.

    At the viewing: Check every warning light goes out, and test the air con and all the electrics.

    Source: What Car?: Mercedes C-Class (2021 on) reliability

Questions to ask the seller before buying a 2023 Mercedes-Benz C-Class diesel

Ask before you travel to see it. A seller who knows the car will have answers, and receipts.

  1. Has the fuel pump recall been done?
  2. Can I see the service history and receipts for any big jobs?

Looking at a Mercedes-Benz C-Class?

Check the actual car: its own MOT history, mileage and what to ask the seller. Free, no sign-up.

Other years

Every year of the Mercedes-Benz C-Class compared

YearMOT testsMost flagged
2026–Too new for MOT data
2025–Too new for MOT data
2024–Too new for MOT data
20224,795Tyres 26%
202111,663Tyres 27%
202030,441Tyres 29%
201973,990Tyres 29%
201884,961Tyres 30%
2017118,916Tyres 30%
2016110,990Tyres 30%
2015103,655Tyres 30%
201477,294Tyres 31%
201372,996Brakes 31%
201281,468Brakes 39%
201160,864Brakes 39%
201042,612Brakes 39%
200941,744Brakes 41%
200844,156Suspension 42%
200739,195Suspension 48%
200631,275Suspension 55%
200527,259Suspension 57%
200420,438Suspension 57%
200314,253Suspension 53%
20027,932Suspension 48%
20014,263Suspension 47%
20001,993Suspension 41%
19992,498Suspension 36%
19982,759Suspension 38%
19972,187Suspension 44%
19961,272Suspension 37%
1995970Brakes 33%
1994779Suspension 37%
1993–Too few tests

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2023–2025, counting the MOTs of Mercedes-Benz C-Class cars first registered in 2023. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score