What can fail an MOT?

Common causes of an MOT failure

The MOT test includes a range of checks from tyres to the headlights.

The Driver and Vehicle Standards Agency (DVSA) reports that almost 30% of all UK vehicles initially fail their annual MOT – often for minor issues that could easily have been prevented.

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Faulty or broken lights will cause an MOT failure. Yet it's easy to check them before the test.

Switch on your headlights, fog lights and hazard lights, and if it's safe to do so, walk around the vehicle and see if they're all working. Don't forget the number plate lamps and the rear lights.

You may need someone to help you with the brake and reversing lights.

On recent cars the daytime running lamps should always be on.

Also check that your lights aren't covered or obscured by stickers.

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Car suspension problems are not easy to spot from the outside.

However, while driving you might start to notice every bump on the road, and an excessive noise when you go over potholes.  

Or the suspension may feel soft when you brake or corner. And even steering becomes hard work.

If you're experiencing any of these issues, to avoid a fail get your car checked by a garage before the MOT.

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Tyres are a common cause of MOT failure for several reasons:

  • Tread – The minimum legal tyre tread depth for cars and vans is 1.6mm in a continuous band around the central 3/4 of the tyre. Any tyre with a tread of less than 1.6mm will fail the MOT test.

  • Damage – If the tyre contains any cuts, or the inner plies and steel belt are exposed, your car may fail. Look also for any bulges or tears in the sidewalls.

  • Sizing – If a tyre is of a different size to its opposite partner, the car is likely to fail. You must also ensure the tyres match the manufacturer specification.

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MOT test from AA Smart Care

When you book an MOT you get:

  • Testing at AA approved garages.
  • Quick and easy online booking and payment.
  • Repair parts and labour are guaranteed for 1 year or up to 12,000 miles.
  • Fair, transparent pricing.

And if you book a service with an MOT, you can get free vehicle collection and return, subject to availability.

If your car does fail its MOT and you'd like us to make the necessary repairs, we can carry out your retest for free.

Author: The AA

Book your MOT test at an AA approved local garage

Free collection and return when you book a service with an MOT, subject to availability. Repair parts and labour are guaranteed for 1 year or up to 12,000 miles.