5 common reasons for MOT fails (and how to fix them)

Mechanic working in auto repair shop
Mechanic working in auto repair shop

Everyone has said a silent prayer as they drive their car to the MOT station, fretting about a flickering light or wondering about a too-bald tyre. Pre-MOT nerves are more common than you'd like to think. However, it is possible to avoid the worry (and a massive MOT bill) by checking and maintaining your car regularly. While some jobs, such as replacing worn brakes, should only be undertaken by professionals, other more simple tasks such as replenishing a vehicle's oil and water can easily be done at home.

AOL Cars spoke to Peter Jones, MOT Manager at Fox Garage to discover the most common reasons for MOT fails. With almost 50 years in the motor trade behind him, Jones has serviced his fair share of vehicles and so knows just what will, and won't pass its MOT. How would your car fare against his list?

Fail #1: Lights not working

"The top failure would have to be lights," said Jones. "Some people just can't be bothered to check their lights before they come into the MOT station and we'll find they've got a bulb out. Whether it be a side light bulb, a stop light bulb, or a head light sometimes, the top failure will always be lights."

To avoid this, you should ask a friend to walk around your vehicle while you activate all the external lights to check that they are working correctly. If any bulbs have gone, eBay is a great place to source low-cost replacements.

Fail #2: Tyres too worn

Jones's second most common reason for an MOT failure is worn or damaged tyres.

"Cars will come in with tyres that are bald on the inner edges, have lumps sticking out of them or are just generally worn out," he explained. "As with lights, people don't look at their tyres."

Before taking your vehicle for its MOT, you should check its tyres. Make sure that the tyre pressure is correct before feeling the surface of the tyres for any irregular lumps or tears. Tread depth can be measured by placing a 20p coin into the grooves of the tyre. If the outer band of the 20p coin is completely obscured when it is inserted, then its tread is above the legal minimum of 1.6mm in depth. If your tyres are worn or damaged, it's worth replacing them before your MOT. Use eBay's tyre finder to select a tyre that's right for your car.

Fail #3: Weak brakes

Brakes take third place on Jones's list. "Cars come in and their brakes don't meet the standard – they're just generally worn out. The pads can be worn down to metal on metal, and the discs are corroded and worn away due to a lack of maintenance," he said.

"Also there are a lot of people with automatic cars who never use the handbrake, instead leaving the car in 'park'. Then when it comes to their MOT the handbrake doesn't work because it has seized solid, and unfortunately the law says you have to have a handbrake that works and it has to meet a minimum standard."

While removing and replacing the brakes on a car can is too complicated a job for the average motorist, the job can be made cheaper by purchasing replacement parts on eBay, and then taking them to a garage to be fitted.

Fail #4: Excessive emissions

"Quite often cars fail their MOT due to emissions and that is simply down to lack of maintenance," said Jones. "The car has to make a minimum level of pollution and if you don't service the car, if the filters, spark plugs and various other components aren't changed, they just get clogged up and they don't run very well. Then the gasses coming out of the back will be polluting and our gas machine will tell you you're out!"

Smoke Coming from Exhaust Pipe of a Car
Smoke Coming from Exhaust Pipe of a Car

Fail #5: Poor steering

For Jones, the fifth most common MOT failure was a tricky one to choose. "There is a part of the steering assembly called the track rod ends. It's a suspension joint that's on the steering so it's a steering joint really. There are two on the car and they can wear through the action of the steering. You'd notice the problem when you suddenly start to get a clunk from the front of the car when you're turning corners."

"Most cars don't fail on anything major, most cars fail on minor bits and pieces," Jones added. By heeding Jones's advice and regularly maintaining your car, your MOT need not be such a daunting prospect.

Prepare for your MOT service with eBay's unbeatable selection of Parts and Accessories. Shop for bulbs, tyres, fluids, and more within eBay's Motor Sales & Events section