Used car guide

2018 Hyundai I800: common problems and MOT failures

What MOT testers find on the Hyundai I800 first registered in 2018: we looked at the 1,181 MOTs these cars had during 2025. Plus known faults and what to look at before you buy one.

1,181MOTs of 2018 cars, done in 2025
66%pass first time (all 2018 cars: 81%)
10,800typical miles a year
8.1×the usual rate for number plate lights

What goes wrong more than usual on a 2018 Hyundai I800?

Parts flagged at MOT more often on the 2018 Hyundai I800 than on all cars registered in 2018.

  • Number plate lights8.1× usual
    Hyundai I800
    14.6% All 2018 cars
    1.8%

    Failed outright at MOT: 5.8%, against 0.6% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £5–£40 our estimate

    At the viewing: Check the number plate lights work and the plates are clean and legal.

  • Sidelights14.6× usual
    Hyundai I800
    10.2% All 2018 cars
    0.7%

    Failed outright at MOT: 10.1%, against 0.6% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £10–£80 our estimate

    At the viewing: Ask a friend to check every light while you work the switches: indicators, brake lights, fog lights and reversing lights.

  • Headlight aim6.2× usual
    Hyundai I800
    10.6% All 2018 cars
    1.7%

    Failed outright at MOT: 10.6%, against 1.7% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £20–£60 our estimate

    At the viewing: Park facing a wall at night or in a garage and check both headlight beams sit level. Aim is a cheap adjustment.

  • Headlights6.5× usual
    Hyundai I800
    7.2% All 2018 cars
    1.1%

    Failed outright at MOT: 6.9%, against 1% of all 2018 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.

  • Engine warning light4.7× usual
    Hyundai I800
    5.2% All 2018 cars
    1.1%

    Failed outright at MOT: 5.2%, against 1.1% of all 2018 cars. The rest were advisories or minor defects.

    Rough price £10–£80 our estimate

    At the viewing: Ask a friend to check every light while you work the switches: indicators, brake lights, fog lights and reversing lights.

Common 2018 Hyundai I800 MOT failures and advisories

The share of 2018 Hyundai I800 MOT tests where testers flagged each area, as a fail or an advisory. Rough prices are typical independent-garage costs.

  • Lights and electrics
    32% of testsRough price £10–£80

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

  • Brakes
    26% 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.

  • Tyres
    25% 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
    9% 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
    6% of testsRough price £80–£250

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

  • Suspension
    4% 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.

Questions to ask the seller before buying a 2018 Hyundai I800

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

  1. Any recent work on the number plate lights? (Flagged at MOT 8.1× as often on the 2018 Hyundai I800 as on other cars the same age.)
  2. Any recent work on the sidelights? (Flagged at MOT 14.6× as often on the 2018 Hyundai I800 as on other cars the same age.)
  3. Any recent work on the headlight aim? (Flagged at MOT 6.2× as often on the 2018 Hyundai I800 as on other cars the same age.)
  4. Can I see the service history and receipts for any big jobs?

Looking at a Hyundai I800?

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 Hyundai I800 compared

YearMOT testsMost flagged
2020–Too few tests
20191,829Lights and electrics 27%
20171,326Lights and electrics 37%
20161,017Lights and electrics 42%
2015153Brakes 43%
2014150Brakes 45%
2013199Brakes 42%
2012904Brakes 49%
2011478Suspension 47%
2010380Brakes 49%
2009142Lights and electrics 58%
2008100Lights and electrics 48%

Where this comes from: the DVSA's anonymised results for every MOT test done in Great Britain during 2025, counting the MOTs of Hyundai I800 cars first registered in 2018. "Flagged" includes advisories, so it isn't the same as a fail rate. How we score