Used car guide

2020 Mercedes-Benz A-Class petrol: common problems and MOT failures

What MOT testers find on the petrol Mercedes-Benz A-Class first registered in 2020 (petrol cars only): we looked at the 225 MOTs these cars had during 2023–2025. Plus known faults and what to look at before you buy one.

Small sample: there were only 225 MOTs of these cars during 2023–2025, so treat the percentages as rough. The known faults below don't depend on it.

225MOTs of 2020 petrol cars, done in 2023–2025
83%pass first time (all 2020 cars: 87%)
6,800typical miles a year
28%had tyres flagged

Common 2020 Mercedes-Benz A-Class petrol MOT failures and advisories

The share of 2020 Mercedes-Benz A-Class petrol MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    28% 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.

  • Brakes
    12% 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.

  • Wipers, windscreen and mirrors
    5% of testsRough price £15–£250

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

  • Lights and electrics
    4% of testsRough price £10–£80

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

  • Suspension
    2% of testsRough price £120–£400

    At the viewing: Listen for knocks over speed bumps, and look behind each front wheel for a snapped coil spring.

  • Oil and fluid leaks
    1% of testsRough price £80–£600

    At the viewing: Look under the engine and on the ground where the car is usually parked for fresh oil or fluid.

Known faults on the 2020 Mercedes-Benz A-Class petrol

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.

  • Many recalls (22 so far)

    All engines

    This A-Class has had 22 recalls, including faulty crankshafts that needed a new engine, leaking turbos, suspension uprights, loose rear axle bolts, the emergency braking system and the panoramic roof.

    At the viewing: Ask a Mercedes dealer to check the VIN, and get proof every recall has been done.

    Source: Auto Express: used Mercedes A-Class (Mk4, 2018 on) review

Questions to ask the seller before buying a 2020 Mercedes-Benz A-Class petrol

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

  1. Have all the recalls been done? Can a Mercedes dealer confirm from the VIN?
  2. Can I see the service history and receipts for any big jobs?

Looking at a Mercedes-Benz A-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 A-Class compared

YearMOT testsMost flagged
2026–Too new for MOT data
2025–Too new for MOT data
2024–Too new for MOT data
2023738Tyres 13%
202218,713Tyres 23%
202160,031Tyres 25%
201925,714Tyres 29%
2018119,754Tyres 32%
2017120,922Tyres 34%
2016113,202Tyres 33%
201579,796Tyres 34%
201468,784Tyres 34%
201343,599Tyres 33%
201215,427Brakes 32%
201116,093Brakes 37%
201018,296Brakes 41%
200920,571Brakes 47%
200819,943Brakes 47%
200717,982Brakes 45%
200613,121Brakes 47%
20058,721Brakes 41%
20043,765Brakes 52%
20033,911Brakes 53%
20022,845Brakes 51%
20011,837Brakes 49%
2000729Suspension 51%
1999496Suspension 53%
1998–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 A-Class cars first registered in 2020. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score