The MOT testing guide

In the UK, over 60% of cars and vans failed* their first-check MOT. But why are so many vehicles falling short of the annual test?

According to government data, faulty steering, brakes and suspension are common failure items when light commercial vehicles are tested. Other issues include worn or damaged tyres, cracked windscreens and faulty lights.

Fortunately, there are some simple at-home checks to increase the chance of a first-time pass and avoid unexpected downtime. Below are the most common reasons for a failed MOT and how to prevent them.

While garages check for a whole host of issues, there are a few easy things you can look for at home.

What is an MOT?

MOT stands for Ministry of Transport (the now-defunct government department), and the annual test checks that your vehicle meets road safety and environmental standards.

Cars and most vans need an MOT when it’s three years old and every year after that. Some historic classic cars are exempt from MOTs which you can read about in our classic car MOT guide.

Vehicle MOT rules and costs

Driving your vehicle or parking on the road without a valid MOT is illegal and invalidates your motor insurance. Many people believe that there’s a 14-day grace period, but this is untrue and if caught, you can be fined up to £1,000. This fine increases to £2,500, plus penalty points, if you’re knowingly driving a dangerous vehicle.

If you’re unsure when your MOT is due, you can use the government MOT checker. You can also sign up for the free MOT reminder service where you'll get a text or email one month before your car, van or motorbike is due for its MOT.

If you’ve forgotten to renew your MOT, you can legally drive to a local test centre. But this must be reasonably close and if stopped by the police you need to prove where you’re driving to.

How much does an MOT cost?

The UK government caps MOT costs depending on the category. Garages don’t have to charge the full amount, with many staying competitive by charging less. Below are the charges for common vehicle MOTs.

• An MOT for vehicles up to 3,000kg gross weight and cars up to eight passenger seats (class 4) is capped at £54.85.
• An MOT for good vehicles (usually vans) from 3,000kg to 3,500kg gross weight (class 7) is capped up at £58.60.

For more information, check the government MOT fees.

How to prepare for your MOT

Here are five effective things you can do at home before your MOT:

1. Clean out the clutter from your vehicle – an examiner can refuse to carry out the MOT if your vehicle is excessively dirty or filled with rubbish.
2. Check your horn work – a broken horn can lead to a failed MOT, so give it a honk before you go.
3. Clean your number plates – both the front and back number plates must be readable to pass.
4. Make sure ALL lights work – check your headlights, tail lights, sidelights, indicators, brake lights, registration plate lights, fog lights and hazard lights and replace them if broken
5. Top up all fluids – your screen wash and brake fluid should be topped up to avoid a failed MOT

Common reasons your vehicle fails its MOT and what to do

Now you know when your MOT is, what happens if you don’t have a valid certificate and quick ways to prepare for an MOT, here are common fail-points and how to prevent them.

Tyre Safe/Adam Fradgley

Tyres

To avoid failing your MOT, you should check your tyre pressure against your manufacturer’s instructions, filling them up if needed to improve handling and braking performance.

You should also check for uneven wear which could indicate a steering fault and affect your vehicle’s ability to grip the road. If one tyre regularly drops pressure, get it checked by your local garage or tyre specialist as it may have a nail or other object in the tread. Look for splits, tears or bulges in the sidewalls as it may be a slow puncture too.

Check your tread depth by placing a 20p coin into the main tread. If you can see the outer border, your tyre is either approaching or has already reached the legal limit of 1.6mm, and you’ll need to replace it. While the legal limit is 1.6mm, 3mm is recommended for driving safely. 

Learn more about getting the right tyres for your vehicle.

Wipers

Inspect the wiper blades physically. If they’re torn or badly worn, causing streaks when in operation, it’s a fail. Replacing broken windscreen wipers may seem daunting, but it’s usually a quick DIY job and can be bought from plenty of car accessory suppliers.

If you don’t feel comfortable changing your windscreen wipers, you can pay someone at a local garage to do it for you. Ask them to show you while they do it so you feel confident about any future changes.

Windscreen

If your windscreen has any chips or cracks, you may be covered by your car or van insurance policy. However, repairs or replacements must be completed before the test date.

Engine management / Airbag warning lights

If your lights are illuminated this might cause your vehicle to fail the test. It’s not usually a DIY fix, so book into your local garage for diagnosis and a repair when possible.

Brakes

Callipers, cables and other components under the vehicle can be damaged by dirt and corrosion, and discs and brake pads or shoes can quickly wear to an unacceptable thickness.

Get your brakes checked if:

• The brake warning light is illuminated on your dashboard
• Your car is pulling to one side
• You hear a high-pitched or metal grinding sound
• You can smell burning carpet
• You feel vibrations and changes in footbrake pedal sensitivity

Suspension

Your vehicle's suspension makes sure you can drive safe and smooth. It absorbs the energy from road bumps to improve your control while driving.

Signs your suspension may need a service:

• Reduced ride comfort and smoothness
• Excessive body roll
• Pulling to the left or right
• Uneven tyre wear
• Knocking noises when driving, particularly on uneven road surfaces

Exhaust, fuel and emissions

An MOT includes a professional emissions test, but you can check noise levels from your exhaust and any excessive smoke.

If you think you have an issue, your local fastfit company can carry out a diagnosis and fit new sections as required, possibly at a lower cost than the garage carrying out your MOT. 

A visibly smoking exhaust can indicate a number of issues, some minor, others more major. This is something you really need professional advice on.

Other ways to avoid a failed MOT

Look at last year’s advisories

Remember those ‘advisory’ items on last year’s pass certificate? No? Well now’s the time to take a look and see what potential concerns the tester spotted.

Unless you’ve had any rectification work done the potential issues will still be there and could well have got worse. A warning about worn brake discs and pads? Get a local specialist to check them out and replace them if necessary.

Servicing

Although it’s another day off the road, a full service perhaps a few weeks before the test may well identify any potential issues, allowing you the opportunity to get them sorted prior to the MOT appointment.

A good technician will point out any areas of concern and discuss with you the options available. When defects are picked up at the MOT, you’re on the back foot – you need the car or van back quickly, with a pass certificate and you might not have the opportunity to have the rectifications carried out the most economical way.