MOT Preparation Checklist: Avoid Common Failures and Save Money

Nearly half of MOT failures are for issues that could have been easily fixed beforehand – often for just a few pounds. Spending 15 minutes checking your car before the test can save you the cost of a retest, the inconvenience of failed appointments, and the stress of unexpected repairs.

Lights: The #1 Failure Reason

Lighting issues account for approximately 18% of MOT failures – yet bulbs cost just a few pounds:

• Headlights: Check both dip and main beam work
• Sidelights and tail lights: Often forgotten
• Indicators: Front, rear, and side repeaters
• Brake lights: Get someone to help you check these
• Fog lights: Front and rear if fitted
• Reversing lights: Often neglected
• Number plate lights: Must illuminate the plate

Tip: Replace any bulbs that are dim or flickering – they may work now but could fail during the test.

Tyres: The Second Most Common Failure

Tyre issues cause approximately 8% of failures:

• Tread depth: Must be at least 1.6mm across the central three-quarters
• Damage: Check for cuts, bulges, or cracks in sidewalls
• Correct inflation: Check against the door jamb sticker
• Matching: Tyres on the same axle should be the same type and size

Pro tip: Use the 20p test – if you can see the outer band of the coin in the tread, you're at or below the limit.

Brakes: Don't Take Risks

Brake issues cause about 10% of failures:

• Listen: Grinding or squealing indicates worn pads or discs
• Check fluid: Brake fluid level should be between min and max
• Handbrake: Should hold on a slope without pulling excessively
• Pedal feel: Should be firm, not spongy or going too far to the floor

Wipers and Washers

Simple but frequently failed:

• Wiper blades: Should clear the screen without smearing or juddering
• Washer fluid: Top up the bottle – must spray effectively
• Washer jets: Check they're aimed at the screen, not the roof
• Rear wiper: If fitted, it must work properly

Mirrors and Glass

• Windscreen chips: Chips larger than 10mm in the driver's view (Zone A) fail; chips larger than 40mm anywhere in the swept area fail
• All mirrors: Must be present, secure, and not significantly damaged
• Rear-view visibility: Remove anything obscuring the view

Dashboard Warning Lights

These are now automatic failures if illuminated:

• Engine management light: Get it diagnosed before the test
• ABS warning: Will cause an automatic fail
• Airbag/SRS warning: Will cause an automatic fail
• EPC (Electronic Power Control): Automatic fail

Other Quick Checks

• Horn: Must work and be audible
• Seatbelts: All belts must work and retract properly
• Doors: Must open from inside and outside, and latch securely
• Exhaust: No excessive noise, smoke, or obvious leaks
• Fuel cap: Must be present and seal properly
• Registration plates: Must be readable, properly spaced, and correctly mounted

Get a Pre-MOT Check

If you're not confident checking everything yourself, we offer MOT preparation service at our Cheddar workshop. We'll check your car for common failure points and fix any issues before you take it for testing. This saves time, money, and the hassle of retests.

Book an MOT preparation check or call us on 01934 440410.