An MOT is a roadworthiness check, not a service. The tester is answering one question: is this vehicle safe and legal to use on the road today? Nothing is taken apart, and no faults are repaired during the test itself.
What the tester checks
- Brakes. Pads, discs, pipes, handbrake and the actual braking performance on a rolling road.
- Tyres and wheels. Tread depth of at least 1.6mm across the central three quarters, condition, correct fitment and secure wheels.
- Lights. Every bulb, plus headlamp aim, which is one of the most common quiet failures.
- Steering and suspension. Play, worn bushes, leaking shock absorbers and damaged springs.
- Bodywork and structure. Corrosion in prescribed areas, sharp edges and insecure panels. This is where accident damage that was never repaired properly shows up.
- Visibility. Wipers, washers, mirrors and chips or cracks in the driver s line of sight.
- Exhaust and emissions. Noise, leaks and the gas reading for your engine type.
- Seatbelts, horn, registration plates and the driver s seat.
Pass, fail or advisory
Defects are graded. A dangerous or major defect fails the test. A minor defect passes but is recorded. An advisory is a warning that something will need attention before long.
Why good cars fail
Roughly a third of failures come down to lighting, tyres and worn wiper blades, all of which cost very little to sort beforehand. A ten minute check of bulbs, tread, screenwash and wipers the weekend before your test is the cheapest MOT insurance there is.
Damage and the MOT
Poorly repaired accident damage causes real failures: misaligned headlamps after a front end knock, corrosion around a badly filled panel, or a boot lid that no longer closes squarely. If your car has been in a collision, have the repair checked by a bodyshop that works to recognised repair standards rather than waiting for the MOT to find it.
Find your nearest approved repair centre or request a free estimate if something needs putting right.