Most common MOT failure reasons

Nearly a third of cars fail the MOT test first time. We reveal the most common reasons why, and examine concerns about the proposal to extend the gap between tests to two years...

MOT garage - Mercedes C-Class being tested

Around 27 million cars undergo an MOT test each year in the UK, and nearly a third of them (29%) fail the first time round, many due to simple items such as blown bulbs that could be rectified fairly easily.

The most common reason for not making it through the MOT test is faults with lights, indicators or other electrical components. This accounted for 25% of the failures listed in Driver and Vehicle Standards Agency (DVSA) data for the financial year ending in April 2022.

Other important safety items are high on the MOT fail list too: 19% of non-passes are due to suspension issues, and 16% are due to problems with braking systems. A further 12% of cars fail because they have worn or damaged tyres.  When it comes to defects that are rated as dangerous by testers, brakes and tyres top the list of areas of concern. 

Most common MOT failure items

Safety concerns over proposed two-year test intervals

Earlier this year, the Government proposed doubling the time between MOT tests from one to two years to help with the cost of living crisis. However, those in the car industry and many drivers have serious concerns about this move, believing it will have serious implications for road safety.

Mike Hawes, chief executive of the Society of Motor Manufacturers and Traders (SMMT), said: “The industry shares the widespread concern over rising prices and the squeeze on household incomes. Safety, however, must always come first, and while today’s vehicles are more reliable than ever, regular MOTs ensure that safety-critical components such as brakes and tyres, which wear out as a result of normal operation, are properly inspected and maintained. 

“Stretching MOT intervals will undermine the safety net at a time when vehicle miles driven are increasing. To ensure the safety of our roads, drivers, passengers, pedestrians and other road users, inspections and maintenance must be carried out annually following their first presentation in year three.”

MOT compliance

And more than half (55%) of drivers who responded to a survey by the RAC said they thought changing the MOT check to every two years was a bad idea, with 98% believing it would result in more unsafe vehicles on the road and 20% saying it would lead to an increase in the number of collisions on the road.

On top of this, 61% of people surveyed thought the MOT test extension would result in more vehicles breaking down, and 58% said it could end up costing drivers more in the long run due to problems or defects going undetected and then becoming more costly to repair.

The RAC warned that increasing the interval between MOT tests could put more lives at risk on our roads. One area they highlighted is the danger of more vehicles being driven around on illegally worn tyres, which could result in them losing grip on the road and not stopping quickly enough when the brakes are applied.

“There is a real danger that if the Government proceeds with these proposals, we could see an increase in the number of collisions and more injuries and deaths due to more unroadworthy vehicles using our roads, and an overall reduction in road safety,” said RAC head of roads policy Nicholas Lyes. 

MOT test centre sign

At present, all new cars must have an MOT test three years after the date of their first registration. The maximum cost of the test is £54.80, although many garages offer discounts on this price.

Below we list the most common reasons why cars fail their MOT test from data supplied by the DVSA. 

Defect category Percentage of defects
Lights, reflectors and electrics 25%
Suspension 19%
Brakes 16%
Tyres 12%
Impaired visibility 9%
Body, chassis and structure 6%
Noise, emissions and leaks 5%
Steering 3%
Seatbelts and other restraint systems 2%
Vehicle identification 1%
Wheels 1%

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Read more: Find to ensure your car passes its MOT test first time >>