Last updated: 13/11/2023 | Estimated Reading Time: 4 minutes
There are many aspects of your vehicle that an examiner will check on your MOT. Any aspects that aren't up to scratch will need to be remedied, at a cost.
Not everything can be inspected yourself or at home, but here we breakdown a few quick checks you can do yourself to give your car the best chance of passing, and save on any potential labour costs. Making these checks regularly will also generally help ensure your car runs well and reduces the need to pay for repairs or claim on your car insurance in the event of a breakdown.
12% of MOT fails are due to tyre issues, so it makes sense to start your pre-MOT check here. You will be checked on tread depth and tyre pressure. Tyre tread must be a minimum of 1.6mm, running continuously all the way around the central 3/4 of each tyre. In a stitch, a quick way to test this is to use the 20p test. Essentially, you just need to place a 20p piece into the main groove of your tyres. If the outer band of the coin is obscured, then your tread is over the legal limit. If the outer band of the coin is visible however, your tyres could be illegal. In this case you should take your car to a tyre specialist, and most likely you'll have to replace them.
It's also a good idea to check the tyre pressure for each tyre, as laid out in your manufacturers manual (and often written on the inside of the driver's door). Tyre insurance can be useful to have if you find that yours aren't up to scratch and need replacing.
The examiner will inspect your headlights, rear lights, licence plate light, hazard lights and indicators to be sure they are all working as normal. You can check all of these lights by turning them on while the vehicle is stationary and walking around the car.
Testing your brake lights is a little more complicated. You may need to ask a friend or family member to look at the brake lights as you press the brake pedal. If you’re on your own, you can reverse, carefully, up to a reflective surface such as a garage door, and check the reflection in the rear view mirror when pressing the brake pedal.
An examiner will fail your car if the number plates are not clean, legible and clearly visible. The letter spacing and font must also be compliant with legal requirements, although this shouldn't be an issue unless you have a custom number plate. Even if you think it's pretty good, it pays to quickly wipe down your registration plate before the test, to give yourself peace of mind.
Your car's wiper blades need to be able to clear any rain water effectively and keep your windscreen clean. The rubber seal needs to be in good condition, without tears or holes. This is an easy, 5 minute replacement at home that could save you hassle at the MOT centre.
Your horn should be loud enough that it could be heard by someone else on the road, and it needs to give off a long, singular tone. Horns rarely fail, but it's worth testing if you haven't used yours in a while. Just make sure there aren't too many people close by when you do try it out!
All seat belts need to be of an appropriate length, and in good working order, to pass the MOT. To test, pull sharply on each belt in turn, and check that they lock into place. This ensures your safety in the event of sharply braking, and would be considered a dangerous fail by an MOT examiner if not in working order.
Chips or cracks larger in length than 40mm are considered an MOT fail. This also applies to any signs of damage wider than 10mm that is within the driver-side wiper's radius. Be sure to have them repaired before your MOT.
Your vehicle must have sufficient levels of engine oil and fuel in order for the MOT examiner to carry out the relevant emissions test. To check the oil, when the engine is cold and the car is parked on a flat surface, pull out the oil dipstick, wipe clean, insert back in for a minute and then remove it. The level should fall between the MIN and MAX lines on the dipstick.
Brake issues are a common cause of MOT failure. Usually this comes down to worn out brake pads, and/or worn or warped brake discs. To check your brakes, try to listen for any unusual sounds while driving, such as grinding or screeching. The feel of your brake pedal can be another indication. on an empty road, perform a brake test. If it feels spongy or doesn't engage quickly when you press the pedal it could be an indication of worn brakes. You may need to top up your brake fluid before the MOT.
Your handbrake will also be checked, and you can test this by applying it on a hill and seeing if it holds the vehicle in place.