What's checked in an MOT?
MOT tests can be a nervous time for any vehicle owner. Will it pass it’s MOT? What will the costs be to get it roadworthy? Your vehicle can fail its MOT for many reasons, some are more serious than others. So if you’re wondering "What is checked in an MOT?" read on to find out
An MOT Test will check integral components of your vehicle to ensure it’s in a roadworthy condition. If your vehicle meets the standards set by the DVSA you will be issued a new valid MOT certificate for the next 12 months. However, depending on your expiry date this could be 13 months.
The majority of MOT failures can be avoided by carrying out a simple MOT check and maintenance before taking your vehicle in for its appointment. View our Pre-mot checklist to see what you should know.
Which areas are checked?
The below image shows a quick overview of all the vehicle components checked during an MOT test.
It’s important to note that an MOT check is not the same as getting your vehicle serviced.
Below is a complete list of all the things that our DVSA approved MOT testers will examine on your vehicle and the key aspects they will be looking at.
Body, vehicle structure and general items
The overall condition of your vehicle will be examined during an MOT test centres to ensure that it is roadworthy.
In essence the MOT test centre will be looking that your vehicle is:
- Free from excessive corrosion or damage in specific areas
- Has no sharp edges present likely to cause injury
The inspection will essentially look to confirm that the towbar is:
- In good condition
- Has no inappropriate repairs or modification
The MOT tester will also check that:
- The 13 pin electrical socket is working correctly
- The speedometer is in good working order
- The engine mountings are secure
For the electrical socket it will be tested to ensure that it activates the trailer parking lights, brake lights, indicators and rear fog lights. When looking at the condition of you towbar the tester will be checking that it is secure and not damaged or corroded.
When inspecting the fuel system the tester will be checking that
- No leaks are spotted
- Pipes and hoses are secure and in a good condition
- Fuel cap fastens and seals securely
If your fuel cap requires the key to open it make sure the tester has access to the key.
The legal limits for emissions vary depending on the age and fuel type of the vehicle with much stricter limits on newer vehicles. The tester will use specialist equipment (gas probe analyser) which is connected to your car’s exhaust whilst the engine is running. It will measure if your car is within the legal limits for carbon monoxide and hydrocarbon exhaust emissions.
If they do not fall within the legal limit you will be looking at a fail.
A visual inspection will also be carried out to check for excessive dense blue or black smoke produced by the exhaust. Noise levels will also be tested.
The exhaust system will be inspected to check that:
- Is secure and complete
- A diesel particulate filter isn't missing where one was fitted as standard
- There are no serious leaks and it’s not too noisy
A legal installation requirement since 1965 the vehicles seat belts will be inspected to check that:
- Mandatory seatbelts are in place
- Are suitable for the vehicle
- Are in a good condition
- Work properly
- They are attached securely
These will be inspected to check that:
- The driver’s seat can be adjusted and remains in place
- All seats are securely fitted and that seat backs can be fixed in the upright position
These will be inspected to check that:
- The door latch is secure in the closed position
- Front doors open from inside and outside the vehicle
- Rear doors open from outside the vehicle
- All hinges and catches are secure and in a good condition
The vehicle will be inspected to check for the minimum number of mirrors, their condition and security. Indirect vision devices will also inspected to ensure they are in full working order, for example, rear view cameras.
Rear view mirrors and wing mirrors must be secure and provide adequate views to the rear and side.
The vehicle will be inspected to check that the boot or tailgate can be closed properly.
Brakes are also a worryingly common area for cars to fail there MOTs. The overall condition of your brakes, pedals and levers will be inspected, as well as any relevant warning lights.
Make sure to listen out for any squealing or grinding when you brake, these are tell tale signs your brakes could do with some attention. Be sure to also check that your vehicle doesn’t pull to one side when braking.
These will be inspected to check:
- Condition of brakes, including inappropriate repairs or modifications
- Their operation and performance (the efficiency test) - the wheels and trims aren’t removed as part of the test
- Anti-lock braking system (ABS) and electronic stability control (ESC) (where fitted)
The MILs or dashboard warning lights will also be checked for the ABS, ESC, electronic park brake and brake fluid warning lights.
Tyres and wheels
These will be inspected to check for:
- Are in good and legal condition
- Tyre size and type
- Tread depth
Spare wheels and tyres are not inspected.
Vehicles first used on or after 1 January 2012 will be checked to make sure the tyre pressure monitoring system (TPMS) MIL is working.
Your registration plates must be secure and clearly legible. It’s vital to ensure that the characters on the number plate can be easily read, and are correctly spaced and formatted.
In summary your registration plate will be checked for:
- Secure attachment
- Characters correctly formed and spaced
Lighting and Signalling
Lighting and signalling issues are and have always been the most common reason for MOT failure. However, they are one of the easiest areas to check before taking your vehicle in.
These will be inspected to check:
- Their condition
- Operation, including high intensity discharge (HID) and light emitting diode (LED)
- The headlamps for cleaning, self-levelling and security
- Headlamp aim
- Main beam warning light working
It’s also important to note that pairs of lights (i.e rear brake) must emit light of the same colour, size and shape. Your vehicle can be failed if one indicator light is a darker orange than the other.
Headlight aim (both dip beam and main beam) should be below the horizontal, so as to not distract and temporarily blind passing drivers.
This will be inspected to check that it closes securely.
Wipers and washers
These will be inspected to check that they work properly so the driver has a clear view of the road.
Ensuring the driver has a clear and unobstructed view of the road is vital. This can even include hanging air fresheners on your rear view mirror, which can be a fail. Leaving your sat nav in place, if it affects the drivers view can also be worthy of a fail.
The windscreen will be inspected to check for:
- The driver’s view of the road
There must not be any damage or obstruction to the view larger than 10mm in the area directly in front of the driver. Outside this area (but within the reach of windscreen wipers), there must not be any damage or other obstruction larger than 40mm.
You’ll also want to check that your windscreen wipers are working as they should, as if they cant effectively clear the driver’s eye line your vehicle will fail its MOT.
One thing that is often over looked here is ensuring your washer fluid levels are at the correct level.
This will be inspected to check:
- That it works properly
- It’s suitable for the vehicle
Steering and suspension
Steering and suspension are areas of common failures, in fact it’s close to 1 In 10 fails is due to steering or suspensions.
Failures in this area can be tricky to spot before your test but it’s not impossible. One thing to try is to visually look at the parts in the dry to see if there are any wet spots on any of components that make up the vehicles suspension system.
The following will be checked by the MOT test centre:
- Their condition
- Steering oil level
- They work correctly
- No inappropriate repairs or modification including corrosion to power steering pipes or hoses
- The steering lock mechanism works properly
The MILs or dashboard warning lights will also be checked for the electronic power steering and steering lock.
Vehicle identification number (VIN)
The VIN will be present on vehicles used on or after 1 August 1980 and can be found on your v5 registration document. The MOT tester will check that the VIN number is displayed and is legible
However, this does not apply for multistage build vehicles (eg van conversion, multistage self-build).
Your VIN number is often found at the bottom of your windscreen, or under the bonnet.
Visible electrical wiring will be inspected to check that it is secure and not be damaged to the point where it is likely to short circuit or become detached.
Your car's battery will also be checked, again to make sure that it is secure and does not show any signs of leaks.
For diesel vehicle owners MOT testers can be slightly trickier. For example, The MOT tester can refuse to test your vehicle if they think that the smoke test may damage your engine.
If you think this might happen, you should tell them before they start the test. The visual checks we recommended above could prove vital here. It would also be beneficial to go to the test with your vehicle's engine fully warmed up and make sure to check our oil level before the test.
Keeping your vehicle maintained and services will also increase the chances of it passing its MOT test, for example, regular oil and filter changes.
Pre MOT Checks
As you can see a lot of checks are simple ones you can quickly do before taking your vehicle in to be tested. Our pre-mot checklist video will walk you through these step-by-step so you can increase the chances of your car passing its MOT.
MOT Reminder Service
We offer a free MOT reminder service so you will never forget your MOT due date again.