Used car guide

2020 MG ZS: common problems and what to check

What gets flagged at MOT on 2020 MG ZSs, from 12,499 tests in 2025, plus known faults and what to look at before you buy one.

12,499MOT tests in 2025
81%pass first time (all 2020 cars: 86%)
7,000typical miles a year
2.1×the usual rate for brake discs

What stands out

Parts flagged at MOT more often on 2020 MG ZSs than on all cars registered in 2020.

  • Brake discs2.1× usual
    MG ZS
    19.1% All 2020 cars
    9%

    Failed outright at MOT: 1.3%, against 0.4% of all 2020 cars. The rest were advisories or minor defects.

    Rough price £150–£350 our estimate

    At the viewing: Look through the wheel at the brake disc: a deep lip at the edge or heavy scoring means they're worn. Feel for judder when braking.

  • Headlights5.5× usual
    MG ZS
    3.3% All 2020 cars
    0.6%

    Failed outright at MOT: 3.2%, against 0.5% of all 2020 cars. The rest were advisories or minor defects.

    Rough price £40–£400 our estimate

    At the viewing: Check both headlights on dipped and full beam, and look for cloudy or cracked lenses.

  • Braking performance3.6× usual
    MG ZS
    3.2% All 2020 cars
    0.9%

    Failed outright at MOT: 1%, against 0.3% of all 2020 cars. The rest were advisories or minor defects.

    Rough price £100–£350 our estimate

    At the viewing: On a quiet road, brake firmly from about 30mph. The car should stop straight without pulling.

  • Coil springs6.5× usual
    MG ZS
    2.6% All 2020 cars
    0.4%

    Failed outright at MOT: 0.2%, against 0.4% of all 2020 cars. The rest were advisories or minor defects.

    Rough price £175–£400 (pair, one axle) ClickMechanic

    At the viewing: Look behind each wheel for a snapped spring coil, and listen for a clunk or twang when turning the wheel lock to lock with the car stopped.

By area

The share of 2020 MG ZS MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Tyres
    34% 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
    25% 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
    9% 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
    8% 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.

  • 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.

  • Seats and seatbelts
    4% of testsRough price £80–£250

    At the viewing: Pull each seatbelt sharply. It should lock, and retract cleanly.

Looking at a MG ZS?

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Other years

YearMOT testsMost flagged
20231,644Tyres 18%
202217,647Brakes 23%
202114,989Tyres 26%
20198,696Tyres 35%
20185,092Tyres 32%

Where this comes from: the DVSA's anonymised results for every MOT test in Great Britain in 2025, counting tests of 2020 MG ZSs registered in 2020. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score