An MOT test is a legal requirement for most vehicles over three years old in the UK. While it can feel stressful, a little preparation goes a long way. Knowing how to prepare your car for an MOT can help you avoid common failures, save money on repairs, and improve your chances of passing first time.
This guide walks you through essential MOT checks you can do at home, explains common failure points, and includes expert advice to help you feel confident before test day.
What Is an MOT Test?
An MOT checks that your vehicle meets minimum road safety and environmental standards set by the DVSA (Driver and Vehicle Standards Agency). It doesn’t assess overall vehicle condition or reliability — only whether it’s safe and legal to be on the road.
According to the DVSA, around 30% of cars fail their MOT first time, often due to simple, preventable issues.
When Should You Prepare for an MOT?
You can book your MOT up to one month (minus a day) before it expires without losing the renewal date. Ideally, start preparing 1–2 weeks in advance to allow time for repairs if needed.
Check Your Lights and Indicators
Faulty lighting is one of the most common MOT failure reasons.
What to check:
- Headlights (dip and main beam)
- Brake lights
- Indicators and hazard lights
- Rear lights and number plate lights
- Fog lights (if fitted)
💡 Tip: Ask someone to help or park near a reflective surface to check brake lights.
Expert insight:
“Lighting issues are among the easiest MOT failures to avoid, yet they remain one of the most common reasons for rejection.”
— RAC Vehicle Safety Team
Inspect Tyres and Tread Depth
Tyres must meet UK legal requirements.
MOT tyre rules:
- Minimum tread depth: 1.6mm across the central three-quarters
- No cuts, bulges, or exposed cords
- Correct tyre size and matching type on each axle
Uneven tyre wear can also indicate alignment or suspension issues that may be flagged.
Check Brakes and Brake Fluid
Brakes are a critical MOT inspection item.
Basic checks you can do:
- Brake pedal feels firm (not spongy)
- No grinding or squealing noises
- Brake fluid level between MIN and MAX
Low brake fluid may indicate worn brake pads or a leak — both can lead to an MOT failure.
Windscreen, Wipers, and Washer Fluid
Visibility-related issues are a frequent cause of MOT failure.
Make sure:
- Windscreen has no cracks over 40mm in the driver’s view
- Wipers clear the screen effectively
- Washer jets work and fluid is topped up
Even an empty washer bottle can result in a fail.
Check Seatbelts and Seats
All seatbelts must:
- Extend and retract smoothly
- Lock when pulled sharply
- Be free from fraying or cuts
Seats must be securely mounted and adjustable if designed to do so.
Test Horn, Dashboard Lights, and Warning Lights
Before your MOT:
- Ensure the horn works
- Check dashboard warning lights turn off after starting
- Investigate ABS, airbag, or engine warning lights
⚠️ Important: An illuminated warning light usually results in an MOT failure.
Expert insight:
“Dashboard warning lights should never be ignored before an MOT — they often signal safety-critical issues.”
— AA Technical Services
Exhaust, Emissions, and Engine Checks
Your MOT includes an emissions test, especially important for petrol and diesel vehicles.
Check for:
- Excessive exhaust smoke
- Loud or leaking exhaust
- Strong fuel smells
A well-maintained engine and fresh oil change before the MOT can help emissions performance.
Steering and Suspension Basics
While a full inspection requires a ramp, you can still check:
- Excessive steering wheel play
- Knocking noises over bumps
- Car leaning to one side
These may indicate worn suspension components or steering faults.
Registration Plates and VIN
Make sure:
- Number plates are clean, readable, and correctly spaced
- Plates aren’t cracked or faded
- VIN (Vehicle Identification Number) is visible
Incorrect plates can lead to an MOT failure.
Clean Your Car (Yes, It Helps)
While cleanliness isn’t part of the MOT, a tidy car:
- Makes inspections easier
- Helps testers spot genuine issues
- Creates a positive first impression
Remove clutter from footwells and boot before the test.
Common MOT Failure Reasons (UK)
According to MOT statistics, the most common failures include:
- Lights and signalling
- Suspension faults
- Brake issues
- Tyres
- Visibility (wipers and windscreens)
Many of these checks can be done at home in under an hour.
MOT Preparation Checklist
✔ Lights and indicators working
✔ Tyres above 1.6mm tread
✔ Brakes feel firm
✔ Windscreen clear and wipers working
✔ Washer fluid topped up
✔ No dashboard warning lights
✔ Seatbelts functional
✔ Number plates readable
Frequently Asked Questions
Can I drive my car if it fails an MOT?
You can only drive it to a pre-booked repair or MOT retest — unless your previous MOT has expired.
Does an MOT mean my car is safe?
An MOT confirms minimum safety standards at the time of testing, not long-term reliability.
Should I service my car before an MOT?
A basic service beforehand can catch issues early and improve your chances of passing.
Final Thoughts
Knowing how to prepare your car for an MOT puts you in control and can save time, stress, and money. Simple checks like lights, tyres, fluids, and warning lights account for many failures — and they’re easy to fix in advance.
As the DVSA advises, regular maintenance throughout the year is the best way to ensure a smooth MOT experience.
