Getting ready for your car’s MOT test? It’s natural to feel a little nervous, especially if you’re not sure what could cause a fail. Every year, many drivers are surprised to learn that their cars didn’t pass due to simple and avoidable problems.
In this post, we’ll go over the most common reasons why vehicles fail an MOT and how you can avoid them. At TJ Services, we help hundreds of local drivers pass their MOT test in Fleet every year by spotting issues early and offering honest advice.
Let’s get started.
What Is an MOT and Why Can Cars Fail?
The MOT (Ministry of Transport) test is a legal check your car must pass every year (after it’s 3 years old). It makes sure your car is safe, roadworthy, and meets emissions standards. If anything major is wrong—like worn brakes or a faulty light—your car will fail the test.
Some issues are considered dangerous, which means the car must not be driven until fixed. Others are major, and still require repairs before you can pass.
The good news? Many of these problems can be fixed before the test—if you know what to look for.
1. Lights and Indicators
Most common cause of MOT failure.
Over 25% of MOT fails are due to faulty lights. This includes:
- Headlights not working or not aimed correctly
- Brake lights or rear lights not working
- Indicators that blink too fast, too slow, or not at all
How to avoid it: Before your test, ask someone to help you check all your car’s lights—headlights, fog lights, indicators, number plate lights, and brake lights. Replace bulbs if needed. It’s a quick fix that makes a big difference.
2. Tyres and Tread Depth
Your tyres must have enough tread to grip the road and keep you safe.
- Legal minimum tread depth: 1.6mm across the central three-quarters of the tyre.
- Cracks, bulges, and uneven wear can also cause failure.
How to avoid it: Use a 20p coin to check tread depth—if the outer rim of the coin is visible, your tyres are too worn. If in doubt, come to TJ Services for a quick tyre check.
3. Brakes
Worn brake pads or faulty brake systems are a serious safety issue—and a common MOT failure.
You might notice:
- Squealing sounds
- Car pulling to one side when braking
- Spongy or unresponsive brake pedal
How to avoid it: Have your brakes checked during regular servicing. We can also test your brake fluid and braking performance before your MOT.
4. Windscreen and Wipers
You need a clear view of the road. Even small cracks or worn-out wipers can cause a fail.
- Cracks larger than 10mm in the driver’s line of sight
- Cracks over 40mm anywhere else
- Wipers that don’t clean properly
How to avoid it: Replace wiper blades if they squeak or leave streaks. Check the windscreen for chips or cracks and get them repaired early.
5. Suspension Problems
Suspension helps your car absorb bumps and keep control. If it’s damaged, the car may feel bouncy or uneven.
Common causes of failure include:
- Broken coil springs
- Worn shock absorbers
- Leaks from suspension parts
How to avoid it: If your car makes clunking noises over bumps or feels unstable, get it checked before your MOT. Our team at TJ Services has the tools to diagnose and fix suspension issues.
6. Exhaust and Emissions
Your car must meet environmental rules. MOT testers check for:
- Excessive smoke (blue, black, or white)
- Loud or broken exhaust
- Emissions that exceed legal limits
How to avoid it: If you notice unusual smoke or a loud exhaust, visit us before your test. We can check your catalytic converter, exhaust system, and sensors.
7. Steering Issues
Loose steering, worn power steering components, or fluid leaks can all lead to a fail.
How to avoid it: If your steering feels heavy or unresponsive, don’t wait for the MOT. Bring it in for a check. We’ll make sure the system is tight and safe.
8. Seatbelts and Safety Features
Your seatbelts must:
- Click and hold securely
- Retract fully
- Not be frayed or cut
How to avoid it: Test every seatbelt in the car before your MOT. Make sure child seats are removed if not needed for the test.
9. Number Plates and Registration
An unreadable or incorrect number plate can fail your MOT.
- Plates must be clean and securely fixed
- The font and spacing must follow DVLA rules
How to avoid it: Clean your plates and check for cracks. If yours is damaged, we can replace it.
10. Warning Lights
Dashboard warning lights matter during an MOT. Common lights that can cause a fail:
- Airbag warning light
- ABS light
- Engine management light (EML)
How to avoid it: Don’t ignore dashboard lights. Visit us at TJ Services, and we’ll scan your car’s ECU to find the cause and fix it before the test.
How We Help You Pass First Time
At TJ Services, we don’t just carry out MOT tests—we help you prepare for them.
Here’s how:
- Free Pre-MOT Checks – We spot small problems before they become big fails.
- Same-Day Repairs – Many issues can be fixed immediately.
- Free Retests – If your car fails and we do the repairs, we’ll retest for free within 10 working days.
- MOT Reminders – Never miss your test again.
We’re a trusted garage in your local area with years of experience keeping drivers safe.
📍 TJ Services 31 Sandy Lane, Church Crookham, Fleet, Hampshire, GU52 8BX
FAQs
Q: Can I drive if my car fails its MOT?
Only if your current MOT is still valid and the car didn’t fail for a dangerous defect.
Q: How early can I book my MOT?
You can book it up to 1 month minus 1 day before your expiry date and keep your renewal date.
Q: Do you offer reminders?
Yes, we’ll remind you every year so you never forget your MOT again.
Final Thoughts
Most MOT failures happen due to small, fixable problems. If you check lights, tyres, brakes, and warning lights before the test, you’ll have a much better chance of passing first time.
At TJ Services, we take the stress out of MOTs. Book your MOT test in Fleet with our expert team today—we’ll help you stay safe and on the road.
📞 Call us or visit 📍 TJ Services 31 Sandy Lane, Church Crookham, Fleet, Hampshire, GU52 8BX
