The Most Common MOT Failures and How to Avoid Them

Written by Petro Olekhnovych, mobile mechanic in Aylesham, Kent

The most common MOT failures are lights and electrical equipment, suspension, tyres and brakes, followed by problems with the driver’s view of the road. DVSA figures for April 2025 to March 2026 show that around 27.5% of initial MOT tests on cars and vans ended in a fail. Many of these faults can be spotted with simple checks before the test.

The latest MOT failure figures

The Driver and Vehicle Standards Agency (DVSA) publishes MOT results for cars, vans and small passenger vehicles. Its figures for the 2025 to 2026 financial year show the share of initial tests that failed in each area:

A car can fail in more than one area, so these do not add up to the overall failure rate.

Tyres and brakes stand out for a worse reason. They cause most “dangerous” defects. In the same year, 4.47% of initial tests found a dangerous tyre defect and 2.39% found a dangerous brake defect.

Back in 2017, the DVSA said nearly half of all MOT faults could be avoided with regular, simple checks such as replacing bulbs, wipers and tyres.

1. Lights and electrical equipment

This is the biggest single cause of MOT failures. Often it is something as small as a blown bulb.

How to avoid it:

• Walk round the car and check every light: headlights, sidelights, indicators, fog lights, reversing lights and number plate lights.
• Ask someone to watch the brake lights while you press the pedal.
• The DVSA suggests giving each light a tap to check it is not loose. Check the colours are correct and match.
• Clean the lenses. The Highway Code says lights, indicators, reflectors and number plates must be kept clean and clear.

2. Suspension

Suspension faults are the second most common reason for failing. Worn parts are hard to see yourself, but there are clues.

How to spot problems:

• Listen for clunks or knocks over bumps or when cornering.
• Check the car sits level and is not lower at one corner.
• The RAC suggests pushing down on each corner. It should settle without bouncing.

If you notice any of these, get it looked at before the test.

3. Tyres

The Highway Code says car tyres must have at least 1.6mm of tread across the central three-quarters of the tread and around the whole tyre.

How to avoid a tyre fail:

• Check tread depth on every tyre, including the inner edge.
• Look for cuts, lumps and bulges.
• Check the pressures match the figures in your handbook.
• Look for uneven wear, which the RAC says can point to alignment or inflation problems.

Tyre faults are not just an MOT issue. The DVSA found that braking and tyre defects made up over 75% of the car defects that contributed to accidents in its 2015 road casualties report.

4. Brakes

The DVSA suggests checking that the brakes work smoothly and that the car does not pull to one side.

Warning signs before an MOT:

• Squealing or grinding when you brake.
• The car pulling left or right under braking.
• The handbrake not holding the car on a slope.

If the brakes feel wrong, do not wait for the MOT. Stop driving and get them checked. Our guide to brake pad warning signs explains what to look out for.

5. Visibility and the driver’s view

How to avoid it:

• Check the wipers clear the screen without smearing, and top up the washer fluid.
• Look for chips or cracks in the windscreen, especially in front of the driver.
• Remove anything blocking your view. The DVSA mentions stickers, toys and air fresheners.

Do not forget the engine warning light

Under the MOT inspection manual, an engine warning light that is not working, or that shows a malfunction, is a major defect on petrol and diesel cars. That means a fail.

If the light is on, get the fault diagnosed before the test.

Give yourself time before the test

GOV.UK says you can get an MOT up to a month (minus a day) before it runs out and keep the same renewal date. Our guide on how early you can MOT a car explains the rules.

Booking a pre-MOT check a few weeks before the test gives you time to fix anything first. Do not let it lapse: GOV.UK says you can be fined up to £1,000 for driving without a valid MOT.

How we can help

We are a mobile mechanic, so we come to your home or workplace. We cover Aylesham, Canterbury, Dover, Deal, Sandwich, Folkestone and nearby villages.

We offer pre-MOT checks to spot likely failures before the test. We also handle brake pads and discs, servicing, and fault finding if your engine warning light is on. For anything outside that, we will tell you what we found and what it needs.

Labour is £30-£50 per hour, depending on the job and its difficulty. Parts are extra. We agree the price with you on WhatsApp before any work starts.

You can also book an appointment here.

Frequently asked questions

What is the most common reason for failing an MOT?
Lights and electrical equipment. In 2025 to 2026, 10.44% of initial car and van MOT tests failed in this area, according to DVSA data.

Can I drive my car if it fails its MOT?
It depends on the defect and your MOT date. GOV.UK says you can drive to or from a repair, or to a pre-arranged test, if your MOT has expired. Never drive a car with a dangerous defect. See what to do if your car fails its MOT.

Will a warning light fail the MOT?
An engine warning light showing a malfunction is a major defect, so yes. Get it diagnosed before the test.

How early can I get my MOT?
Up to a month (minus a day) before it expires, and you keep the same renewal date.

Need help? Send a WhatsApp to 07563 350335 with your car’s make and model and we’ll come to you.

Sources

• GOV.UK: MOT testing data for Great Britain (DVSA)
• DVSA: MOT class 3 and 4 vehicles, initial failures by defect category (CSV)
• GOV.UK: MOT fails could be avoided by basic car maintenance
• GOV.UK: Getting an MOT
• GOV.UK: The Highway Code, Annex 6 Vehicle maintenance, safety and security
• GOV.UK: MOT inspection manual, section 8 Nuisance
• RAC: The most common MOT fails and how to avoid them