What Does An MOT Check?

What do They Check on Mot?

You know you need to have an MOT every year but do you actually know what the tester is checking for? For obvious reasons, the test is very thorough with the car checked all over. The following gives you a good idea of what will be checked on your MOT test.

VIN Number

This is a number that is unique to your vehicle, it is also sometimes called the chassis number. You can have it in more than one place, but you can’t have more than one VIN number.¬†Cars that were first registered on and after the 1st of August 1980 have to have the number permanently displayed in a readable condition.
Typically it would be under the bonnet, attached to the slam panel.

Vin Number Mot Llandudno

An example Vin Number for a Porsche.

UK Number Plate Explained

Registration Plate

There are various rules and regulations that apply to your number plate, falling foul of them is an MOT failure and a potential £1,000 fine.
The numbers and letters need to be the right size and height and the spacing is also important.IF you have a private plate the rules still apply, so be careful. You might struggle to find places that will print an incorrect place as it can cost them their permission to carry on making them.


The condition and operation of your vehicles lights will be put to the test. Are the aimed correctly and is the warning light for the main beam working? The tester will also look at the colour that they shine and the pairs of lights must give out the same colour and be the same shape and size.

Car Headlights must work.

the steering wheel and suspension are very important to pass an mot test

The steering wheel and suspension are looked at closely.

Steering and suspension

There are various checks made to cover this part of the test. The inspector will be very keen, as you’d expect, to make sure the steering and suspension are in good condition. The poking around includes areas and parts inside the car as well as under it and under the bonnet. Being such vital parts to the safe use of a vehicle all parts need to be in good working order, not showing signs of excessive wear and tear.

Wipers and Washer bottle

Not everyone realises this but running out of washer liquid (water or special detergent) can fail your MOT on its own. Apart from that the wiper blades need to be in good working condition and the jets the fire the fluid on the screen must be working and not blocked, again this can be a fail on your test.

windscreen wiper, checked as part of the mot test.

Windscreen wipers and fluid bottles are checked.

The horn of a car will be tested

The horn will be tested to make sure it sounds.


It’s fairly obvious what needs to happen here. If the horn doesn’t sound when a button or switch is pressed inside the vehicle cabin, it’s a fail.


The MOT is not just about keeping other road users safe by being sure your vehicle is roadworthy, it’s also keeping you safe, too. If a belt has frays or tears you are looking at a fail. Inertia belts need to work as expected and all mountings need to be secure. The belts in the back must also work, it’s not just about the front seats.

car seatbelt

Seatbelts in the front and back must function properly.

car fuel filler cap.

Fuel filler cap and fuel system, vital for the test.

Fuel System

Another crucial area of the test comes around the fuel system. Every aspect of it will be checked for proper workings and to make sure there are no leaks. The tank and pipes must be in good condition for obvious reasons. The right fuel filler cap has to be there, the wrong one is a fail.


The majority of vehicles have to pass emissions test to receive an MOT certificate. If you drive a petrol vehicle that was used before August of 1975 or a diesel used before August 1979 the test is by sight. Emissions can be tested on roadside checks, too. If you fail those you have 10 days to get it rectified or you face prosecution.

emissions test for the car mot

Emissions must fall within specified limits to pass.

bodywork is part of the mot

Bodywork must be in a safe condition.


The general condition of the body work is checked by the tester. If there are significant amounts of damage or rust in certain places that can mean a fail. So can sharp edges anywhere on the bodywork.


The front doors on the vehicle should be able to be opened from both the inside and outside. The door latch needs to hold it securely when closed.

The car doors must work properly

Car doors must be functional.

The wing mirrors of vehicles have to be in good condition and secure.

Car wing mirrors; very important to help drive safely.


Wing mirrors are very important to being able to drive a vehicle safely, so your car can fail if they are not in good condition.

Wheels and Tyres

These need to be checked on several important points to pass the test. The condition and depth of tread are two areas that will be looked at by the tester.

vehicle wheels and tyres need be in good condition.

Wheels and tyres, all need to be in good condition.

brakes need to work properly.

Vehicle brake systems – clearly, they need to work!


The brakes will be tested to ensure the vehicle can stop within guidelines and safely.