The vast majority of ‘dangerous’ MOT failures are down to issues with tyres and brakes, according to research by the RAC. The motoring organisation’s study revealed problems with lights and reflectors cause most failures, but the most serious failures tend to be caused by faulty brakes or tyres.

Overall, the RAC’s analysis of Driver and Vehicle Licensing Agency (DVLA) figures revealed 25 percent of all MOT failures in the 12 months to March 22 were down to lights, indicators and reflectors, while faulty or broken suspension made up just under a fifth (18.3 percent) of failures. However, the most serious category of MOT failure – designated ‘dangerous’ – was most commonly caused by brake or tyre defects.

In fact, nine in every 10 ‘dangerous’ defects (88 percent) recorded by MOT testing stations were related to either tyres or brakes. And the proportion of MOT failures caused by tyre defects has risen slightly, up from 10 percent in 2018-19 to 12 percent in 2021-22. Brake problems caused 17 percent of all MOT failures, making them the third most common problem.

MOT testing station sign in the UK

Defects categorised as ‘dangerous’ mean the car cannot be driven again until remedial work has been carried out, and the RAC’s figures suggest almost one in 10 MOT tests (eight percent) find at least one dangerous fault. Overall, DVLA figures show a third of initial MOT tests are failed for one reason or another.

RAC head of roads policy Nicholas Lyes said although MOTs could be expensive for motorists, getting issues sorted as soon as they arise could prevent bigger bills in the future. He also said routine servicing would reduce the chances of failing an MOT.

“Many drivers dread taking their vehicle for its annual MOT for fear they could end up having to spend lots of money on repairs in order to get it to pass,” he said. “This is no doubt the case for an unlucky third of owners whose vehicles fail their MOTs initially.

“Drivers should never ignore dashboard warning lights as they could end up putting themselves or others at risk and costing themselves a lot of money with a bigger repair bill than necessary had they acted straightaway. Additionally, routine servicing helps reduce the chance of a vehicle failing its MOT as it includes a host of important basic checks.

“It’s also advisable to have someone check rear lights and indicators are working if the vehicle does not have modern dashboard warning lights. Keeping tyres properly inflated and having a smooth driving style will often help prolong the life of the rubber. And if something doesn’t sound or feel right, get it checked at a trusted garage as soon as possible.”

MOT test