The most common MOT failures | First Stop Blog

The most common MOT failures (and how to avoid them)

Look, it's hard not to worry about your MOT test. After all, it does determine whether your car is legal and fit for the road. But so many motorists are oblivious to what is included, which can set you up for a fail. 

Because here's the thing: not all MOT failures are out of your hands. That’s right! You can prevent three of the five common failures highlighted in this post by doing some simple checks at home. 

And with that in mind, let’s get going. 

Why is an MOT important? 

First off, it’s a legal requirement. All cars older than three years must pass a yearly MOT test (unless it was made before 1960). An MOT is a simple test of roadworthiness. In it, the tester will check that your car meets the legal requirements set out by the Driving and Vehicle Standards Agency (DVSA). 

But while it covers all the vital car components, it won’t reveal anything like a slipping clutch or a problem with the engine. Or anything that could cause a breakdown in the future, for that matter. No. For this, you’ll need to book your car in for an interim, a full or a major service. 


Now, what are the most common MOT failures? 

Lights and signalling (18.9%) 

Almost a fifth of cars fail because of a light or signalling problem. Often, it’s something as simple as a faulty bulb. Which, when you think about it, is totally avoidable. 

A quick walk around your car at night is all it takes to avoid this. Ask a friend or relative to help with your brake and reverse lights. Or pull up in front of a glass window and look through your rear-view mirror. Oh, and pay attention to your number plate lights, as you won’t pass without them. 

Check the condition of your lights too. Look for mist, cracks and lingering condensation. If the cases are misty (or dirty), you should give them a clean before your MOT. 


Suspension (13%)

With so many potholes in UK roads, there’s no surprise that one in ten MOT failures relates to a suspension issue. But it’s not just the poor UK roads that are to blame, though. 

Suspension issues are incredibly hard to notice, so you’d be forgiven for turning up to an MOT with a leaky shock absorber or even a snapped spring. But you should look for them. 

Suspension faults can affect your tyres too, so it’s vital for road safety. The trick here is to listen to your car when you drive — especially round corners and over bumpy roads or speed bumps. You’ll hear a clunky sound if there’s a problem. 

Also, have a walk around your car and press down on each corner. Check that it’s sitting correctly, and evenly. 


Brakes (9.6%)

Your brakes are one of, if not the, most critical safety car component. So it’s surprising that one in ten cars fail because of a brake issue. It’s worrying as well, as a fault with your braking system is relatively easy to detect. 

The most common signs of a brake fault are a squealing or grinding noise, both signs that your brake pads are low. Another sign is veering to one side under braking. 

But it’s not just the pads that wear out. Inspect your brake discs by looking through the spokes or removing the wheel if you can’t see. The surface of the disc should be smooth, and they shouldn’t be badly scorn or uneven. If you’re unsure, head to your local First Stop garage and let us take a look. 

And don’t forget the handbrake. It sounds obvious, but make sure it holds the car on a hill. If it doesn’t, you should get it looked at right away. 


Tyres (7.7%)

Without four good tyres in good condition, your car’s performance will suffer, yet they’re the fourth most common MOT failure. You should check your tyres every 2-3 weeks, not just before an MOT. 

All you need to do this is a 20p coin, so there aren’t any excuses. Here’s how to do it: 

  • Place a 20p coin into the main groove of your tyre
  • If you can’t see the raised edge of the coin, your tyre’s tread is likely above the minimum legal limit of 1.6mm. 
  • If you can see the raised edge, you should get your tyre checked out by a professional as it could be illegal and unsafe. 

Don’t just rely on what you can see, though. Feel inside each tread groove for any signs of uneven wear. This can be a sign of poor alignment or under or overinflation. And while you’re doing this, keep an eye out for any cuts, bulges or cracks. All of which can lead to a blowout and an MOT fail. 


Driver’s view of the road (7.2%)

This is possibly the most shocking of the bunch. A whopping 7.2% of cars fail because of something blocking the driver’s line of vision. The driver’s eye line must be completely clear. Clear of chips, cracks, phone cradles and aftermarket sat-navs. 

A chip (or crack) bigger than 10mm is a fail. Up to 40mm is safe outside the driver’s line of vision (but inside the area swept by the wipers). Talking of windscreen wipers, make sure they work, and that they leave your windscreen smear-free. You should have plenty of washer fluid too. 

Your rear-view mirror is another thing to look at, it needs to be intact and adjustable if you’re going to pass.


Book your MOT

So those are the most common MOT failures. But while these are the most common, there are a load of other components that the MOT tester will check. Some you can check at home before you take your car to the garage, so it’s worth knowing. Likewise, how to prepare for an MOT test

If you haven’t already booked your MOT test, locate your local First Stop garage here