Pre-MOT Checks & Guide

Many of the most common causes of MOT failure are things that you can easily check for yourself.

Windscreen chips & damage

There are two different areas to look for damage to your windscreen: the area immediately in the driver’s field of view & the surrounding area outside of that. If there’s a chip in the glass right in the driver’s field of view it has to be less than 10mm in diameter to pass an MOT. Outside of that zone, cracks in the windscreen need to be less than 40mm in diameter to be within safe and legal limits.

Windscreen wipers

Your windscreen wipers are tested to make sure that they can clear enough of your forward view when driving in the rain. Your windscreen washers are also tested to check that they spray enough liquid on to the glass. It’s important to make sure that they are in full working order before the test and it’s worth making sure you have enough screen wash in your car to perform the test.

Tyre check for legal requirements

Tyres are assessed on a number of criteria relating to whether or not each tyre is safe to use on the road. It should be immediately apparent if a tyre is bald, but you can easily check how much legal tread you have left on your tyres before your MOT.

You can check your tread is within the legal limit of 1.6mm with a 20p coin: if you put the coin in between the tread on your tyres and the coin’s outer ‘band’ doesn’t show at all, your tyres should be within legal tread limits.

Many tyres have tread depth indicators between the tyre tread to make it easier to see how close your tread is to its legal limit. The indicator looks like a bar between the ‘trenches’ of your car’s tread patterns; if your tread is worn down enough that the indicators are flush with the tread, creating a bridge, your tyres are on or near the minimum legal limit and most likely need replacing.