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Failing an MOT can be frustrating and costly, but knowing the common reasons why cars fail MOT tests can help you prepare and pass the first time. Here are the most frequent causes of failure and how to avoid them.

1. Faulty or Blown Bulbs

Problem: Headlights, brake lights, or indicators not working.
Fix: Regularly check all lights and replace bulbs before your MOT.

2. Tyre Issues

Problem: Worn-out tread or incorrect tyre pressure.
Fix: Ensure tyres have at least 1.6mm of tread and are correctly inflated.

3. Brake Problems

Problem: Worn-out brake pads or faulty brake components.
Fix: Have your brakes checked before the MOT if you notice squeaking or reduced braking power.

4. Windscreen Damage

Problem: Cracks over 10mm in the driver’s view or damaged wipers.
Fix: Repair small chips and replace wipers if they’re streaking.

5. Emissions Failures

Problem: High exhaust emissions due to a faulty catalytic converter or sensor.
Fix: Ensure your car has had a recent service and clean fuel injectors if needed.

6. Suspension Issues

Problem: Worn-out shock absorbers or leaking suspension components.
Fix: Listen for knocking sounds and check for uneven tyre wear.

7. Number Plate & VIN Issues

Problem: Missing, damaged, or incorrect plates.
Fix: Ensure your number plate is legible and properly fitted.

Book an MOT for Less with Rooster

Worried about failing your MOT? Now that you know the common reasons why cars fail MOT tests, you can book a service or a repair with the Rooster app. Rooster helps you save up to 50% on MOT tests, servicing, and repairs—so you’ll get the best price.

Download the Rooster app today and book your MOT with confidence!

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