MOT Preparation Checklist

Top Causes of MOT Failure

1. Lighting and signalling, 29% of failures
2. Suspension, 13%
3. Brakes, 10%
4. Tyres, 7%
5. Exhaust and emissions, 7%
6. Driver's view, 6%
7. Steering, 5%
8. Wipers and washers, 4%
9. Seat belts, 3%
10. Registration plates, 2%

DIY Checks Before Your MOT

Lights

• Walk around the car with all lights on, check both headlights (dipped and main beam)
• Both brake lights (get someone to press the pedal, or reverse up to a wall)
• Both front and rear indicators (all four corners)
• Hazard lights
• Rear fog light (at least one working)
• Both rear lights
• Number plate lights
• Reversing light (engage reverse gear)

Replace any blown bulbs before the test, bulbs cost £2–10 and take minutes to fit on most cars.

Tyres

• Tread depth, minimum 1.6mm across the central three quarters of the tyre. Use the 20p test.
• Check all four tyres for cuts, bulges, lumps, or exposed cords
• Check tyre pressures are correct

Windscreen

• Any chip or crack in the driver's direct view zone wider than 10mm is a fail
• Any chip or crack in the remaining swept area wider than 40mm is a fail
• Get windscreen chips repaired before the test, free if you have comprehensive insurance

Wipers and Washers

• Wipers should clear the screen cleanly with no large missed areas or heavy streaking
• Washer fluid reservoir must have fluid and the jets must spray onto the screen

Horn

• Test the horn, it must work and emit a consistent sound

Seat Belts

• Test every seat belt in the car, pull sharply, it should lock. Let go, it should retract fully.
• Check for fraying, cuts, or damage to the webbing
• Check buckles click and release properly

Registration Plates

• Both plates must be clean and fully readable
• Must use the correct standard font (no custom fonts)
• Rear plate must be illuminated at night

Mirrors

• Driver's mirror (internal or external) must be present and adjustable
• At least one additional mirror giving a rear view to the right side
• No severe cracking

Fuel Cap

• Must seal properly, a loose or missing cap can cause an emissions failure

Warning Lights

• All warning lights should illuminate when you first turn the ignition on, then go out once the engine starts
• Any safety-related warning light that stays on is an automatic MOT fail, this includes engine management, ABS, airbag/SRS, and brake system lights

What Happens If It Fails?

• Advisories, Items noted for attention but not a fail. You can still pass with advisories, but should address them at your next service.
• Minor defects, Listed in the report but not counted as a fail.
• Major defects, The car fails the MOT. Can usually be repaired and retested (often free retest within 10 working days at the same garage).
• Dangerous defects, You cannot legally drive the car away from the test centre.