What Is Checked in an MOT?

There are many checks carried out in an MOT to make sure your car is roadworthy, and these can be grouped into eight categories.

If your car's MOT is coming up, you can find a reliable local garage using FixMyCar.

Lights, reflectors and electrical equipment

Lights

Make sure your front, brake, rear, fog, indicator, registration plate lights and rear reflectors are:

• Correctly positioned and secure

• Not obscured

• In good condition

• The correct colour (a bluish tinge to front headlights is acceptable)

• Not overly affected by the operation of any other light

• Light up at a single operation of the switch

Pairs of lights must have the same colour, shape and size.

Both the dip beam and main beam headlight aim should be below horizontal to ensure it doesn’t dazzle other drivers.

Horn

The horn must sound a continuous uniform note. It must be loud enough to be heard by another road user.

Battery

The battery must be secure and free from leaks.

Electrical wiring

Wiring should be secure. It must not be damaged in a way that it is likely to short circuit or become detached.

If you think you’ve got an issue with your wiring, you might want to have an auto electrician look at your car before its MOT.

Steering and suspension

Steering

During the test, the strength and condition of the steering system will be challenged by pushing the wheel in various directions. Components will also be inspected for wear or damage.

Wheels with locking devices will be tested to ensure they only lock when the engine isn’t running. Plus, cars with power steering must have the minimum power steering fluid level in the reservoir.

Find out how a car's steering works.

Suspension

Your vehicle’s suspension components and shock absorbers will be checked for excessive corrosion, distortion and fractures. Repairs should always be done by a professional to ensure safety.

This guide explains how a car's suspension system works.

Brakes

During an MOT, the condition of the brakes, pedals and levers is inspected. Any dashboard warning lights are noted, and a brake performance test is carried out.

Here are five brake problems you shouldn't ignore.

Tyres

Tyre tread depth must not be below the legal limit of 1.6mm. Tyres will be examined for cuts over 25mm, alongside lumps, tears, exposure of the cord and tread separation. Furthermore, the warning light must operate correctly for vehicles with run-flat tyres.

Read our ultimate car tyres guide for more information about how to inspect and care for your tyres.

Seat belts

Each seat belt and its fittings are checked for their security and condition.

Vehicle body and structure

A general inspection is made of the body, chassis, engine mountings, seats and doors to ensure all components are corrosion-free and do not have sharp edges that may cause injury.

Registration plates

Registration plates must be fitted at the front and rear of the car. They must be secure and legible to someone standing 20 metres away. The characters on the plate must be correctly formed and spaced so that they are not likely to be misread.

Vehicle Identification Number (VIN)

Every car must have a legible VIN permanently displayed on the VIN plate, body, or chassis.

Learn more about what a VIN number is & how to find it.

Speedometer

The MOT tester will check if a speedometer is fitted and can be illuminated. They will also check to see if any cracks in the glass obstruct the view of the speedometer.

Exhaust, fuel and emissions

The exhaust system is inspected to ensure it is secure and doesn't leak. The catalytic converter must be present on vehicles required to have one by law.

If you've got questions about what a catalytic converter is and how it works, this guide is for you.

Fuel system

The fuel system is inspected for leaks. If your tank cap does not seal properly, your car will fail.

Emissions

The tester will use a gas analyser probe while the engine is running to test the smoke emitted from the exhaust. Carbon monoxide and hydrocarbon emissions must fall within the legal limit. Excessive blue or black exhaust smoke will cause your car to fail.

Find out why MOT tests include an exhaust emission test.

View of the road

Mirrors and wipers

The vehicle’s rear-view and wing mirrors must be secure and provide acceptable views to the rear and side while driving.

The windscreen wipers should sweep a wide enough area on the widescreen to give an adequate view of the road - find out how to clean & change them here.

There must not be any damage or obstructions larger than 10mm around the windscreen directly in front of the driver. Your car will fail if there is any damage larger than 40mm. Read our ultimate guide to car windscreens for more information.

Is it almost time for your car's MOT? Find a reliable test centre using the UK's most trusted garage network on FixMyCar.

Frequently asked questions

Why do cars need an MOT?

An MOT proves that your car meets the minimum acceptable environmental and road safety standards required by law to drive it on public roads. 

How can you check a car's MOT history?

You can check the MOT history of a vehicle on the government website here.

How long does an MOT take?

An MOT will usually take around an hour to complete, but this also depends on whether your car passes first time.

When does a new car need an MOT?

A new car needs an MOT after three years.

Can you drive a car without an MOT?

It is illegal to drive without a valid MOT; this is one of the most common driving offences, and if you're caught, it will usually result in a £1,000 fine.

Can I tax my car without an MOT?

In a word, no. To tax your vehicle it must have a valid MOT certificate.

If you found this guide helpful, you might also like:

• When can I MOT my car?

• Can mobile mechanics do MOTs?

• How much is an MOT?

• Common MOT fails & how to avoid them

• What should I do if my car fails its MOT?

• Do electric cars need an MOT?

• What happens if you drive without an MOT?

• Why do MOT tests include an exhaust emission test?