The Mercedes A-Class is a compact premium hatchback — one of the most popular cars in the UK across all segments. The W176 (2012–2018) and W177 (2018–present) are both very common. The W177 generation transformed the A-Class into a genuinely premium product with a class-leading MBUX infotainment interior. Competing with the Audi A3, BMW 1 Series and Volvo V40. Available as hatchback, saloon (A-Class Saloon) and in high-performance AMG A35 and A45 variants. A favourite with younger premium buyers and company car drivers.
Quick Facts — Mercedes A-Class
Common Engines
1.3 petrol (A180/A200), 2.0 petrol (A220/A250), 1.5 diesel (A180d), 2.0 diesel (A200d/A220d), AMG A35 2.0T, AMG A45 S 2.0T
6 Most Common Mercedes A-Class Problems
These are the faults most frequently seen on the Mercedes A-Class by UK garages — ranked by how commonly they occur and what they cost to fix.
Diesel A-Class models on short urban journeys develop DPF blockages very regularly — a compact premium diesel hatchback used as a city car is one of the worst DPF scenarios.
💷 Typical repair cost: £150–£1,200
The 7G-DCT dual-clutch automatic on W177 A-Class models is a well-known source of low-speed judder and hesitation — particularly in slow traffic. One of the most common complaints about the current A-Class generation.
💷 Typical repair cost: £400–£2,500
The MBUX infotainment system in the W177 A-Class — while class-leading when working — has a higher failure and reboot rate than most rivals. Control unit replacements are needed on some examples.
💷 Typical repair cost: £200–£1,500
W177 CDI diesel models require AdBlue. Sensor faults and running low cause warnings and restarting prevention.
💷 Typical repair cost: £10–£700
The mechatronic unit controlling the 7G-DCT dual-clutch can fail on higher mileage examples — causing loss of drive or gearbox warning lights.
💷 Typical repair cost: £600–£2,000
Front suspension knocking over rough roads is reported on higher mileage W177 models — strut top mounts are usually the cause.
💷 Typical repair cost: £100–£350
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Mercedes A-Class — MOT Tips
DPF warning is an automatic MOT fail on diesel models. AdBlue warning is MOT-relevant. 7G-DCT gearbox warning lights must be clear. MBUX system faults can affect ADAS functionality — all driver assistance systems must be operational. EML is an automatic fail.
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Mercedes A-Class Tyres
Most Mercedes A-Class models run 205/55 R16 or 225/45 R17 or 235/40 R18 or 235/35 R19 depending on trim level and year. Always check the placard inside the driver's door for the exact size for your vehicle.
Summary
The W177 A-Class is a genuinely premium and desirable compact hatchback. The 1.3 petrol A200 manual or the 2.0 A250 are the most satisfying powertrain choices. Avoid the diesel for city use. The 7G-DCT auto judder is the most commonly reported issue — the manual gearbox sidesteps this entirely. MBUX failures are worth budgeting for on out-of-warranty examples.
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