MOT defects explained

MOT certificates use technical wording. These guides explain the most common advisories and failures in plain English: what each one is, why it matters, and what to look at when you view a car.

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Brakes

Pads, discs, pipes, hoses, the parking brake and brake warning lights.

Tyres and wheels

Tread depth, tyre condition, wheel bearings and tyre pressure warning lights.

Suspension and steering

Springs, shock absorbers, bushes, ball joints and the steering rack.

Lights and number plates

Headlamps, indicators, brake lights, number plate lamps and the plates themselves.

Windscreen, wipers and mirrors

Anything that affects the driver's view of the road.

Body and structure

Corrosion, sharp edges, doors and anything fitted to the body.

Exhaust and emissions

Exhaust leaks and mountings, emissions and engine warning lights.

Seat belts, warning lights and other checks

Seat belts, airbags, the horn, fluid leaks and the battery.

What the MOT categories mean

Dangerous: A direct and immediate risk to road safety, or a serious impact on the environment. The car fails and shouldn't be driven until it's repaired.
Major: It may affect the car's safety, put other road users at risk or harm the environment. The car fails and should be repaired straight away.
Minor: No significant effect on safety or the environment. The car passes, but it should be repaired as soon as possible.
Advisory: Something to keep an eye on that could need repairing in future. The car passes.

General information about MOT defects, not advice about a particular car. Have any car you're buying inspected by a qualified mechanic.