Keeping your car on the road means investing money in servicing, taking care of the vehicle and crucially keeping your tax, insurance and MOT up to date. The latter often causes dread as you build up to the deadline, and not getting your car serviced or checked prior leaves you wandering into the unknown when dropping your car off.

Part of that pre-MOT anxiety can be the mechanics who you are trusting to not only check your car but not rip you off if fixes are required. If you’re looking in the South of England then you will have access to a variety of providers, take your time when selecting the best mot in

 Southampton and the surrounding areas.

But what are the most likely reasons you car will fail it’s MOT? Here we break down the 5 most common causes for a car failing, and give some advice on the best steps to take to prevent a retest.

Bulbs & Lights

Failure due to broken or malfunctioning bulbs and lights is the most common reason for an MOT failure. While many drivers could easily check their car prior to a test it doesn’t stop it from contributing to around 30% of MOT failures.

Modern cars often notify you when a light has gone out, so for most there is now less danger of wandering into an MOT unawares. If you have a few basic tools, and the correct bulb replacement, then the process of changing them is usually fairly simple.

Certain models require in depth deconstruction to replace something as simple as a headlight. In those cases it may be wiser to book in for a replacement just prior to your MOT, this means you save two trips to drop off your car and you will have a bit more reassurance that you’re likely to pass.


An easy way to fail your MOT at the first step is having tyres that are not within the legal specification. 10% of all UK failures are on issues relating to tyres, so it’s worth carrying out a quick self assessment before booking in your MOT.

You don’t have to be a trained mechanic to make a good assessment of a tyre, check the sidewalls for cracking, debris and bulges in the sidewall. Any major findings would be best discussed with your garage to arrange a repair or replacement.

The final, crucial tyre check prior to the MOT is the classic 20p test. Place the coin in the tread of the tyre, the outer ring of the 20p should be comfortably covered by your tread,

alternatively you can also buy specific tools that will tell you definitively if your tyres are under the legal limit.

Driver visibility (including wipers, windows and mirrors)

Being able to clearly see the road, people and other vehicles is crucial. Anything that prevents you from being able to fully see while operating is considered a failure. Even a faulty wiper results in a failure, as your driving visibility in the rain would be seriously impeded.

Furthermore it’s been known for cars to fail because of an oversized air freshener. While having one dangling from your rear mirror as your drive is a novelty, it’s also an obstruction to your view of the road. MOT testers will not remove these when you bring your car in, they must test the car as it is when you bring it in.

What won’t be checked on my MOT?