What Are the Most Common Reasons That Cars Fail Their MOT?
Thousands of cars fail their MOT every year for preventable reasons. Understanding the most common failure points helps you prepare your vehicle before visiting the test centre.
1. Faulty Brakes: Worn pads, damaged discs, low fluid, or imbalanced braking force all lead to an instant fail. Listen for squeals, grinding, or pulling under braking and have problems fixed promptly.
2. Worn Tyres: Tyres must have at least 1.6mm tread depth across the central three-quarters and show no cuts or bulges. Underinflated or mismatched tyres can also raise concerns.
3. Lights and Indicators: Broken bulbs, misaligned headlights, or cracked lenses remain one of the simplest reasons for failure. Check every light, including fog and reversing lamps, before the appointment.
4. Emissions and Exhaust Issues: Excessive smoke, a damaged catalytic converter, or exhaust leaks will not pass the test. Regular servicing keeps the system efficient and compliant with legal limits.
5. Suspension Problems: Worn shock absorbers, broken springs, or noisy suspension joints compromise handling and safety, so they are closely inspected.
6. Windscreen Damage: Cracks or chips in the driver's line of sight, or significant damage elsewhere, are classed as dangerous and will fail immediately.
Track historic advisories and outstanding issues using our MOT Check tool so you can fix them before the next inspection.
Conclusion
Most MOT failures stem from predictable maintenance problems such as brakes, tyres, lighting, emissions, and suspension. Staying proactive and reviewing your vehicle's history reduces surprises and keeps you on the road. Revisit the MOT Check page regularly to see when the next test is due.