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This blog post was published under the 2015-2024 Conservative Administration

How the new MOT defect categories will work

Posted by: , Posted on: - Categories: Changes to the MOT test, MOT testing service

MOT changes from 20 May 2018 graphic


Today (20 April 2018) marks 1 month to go until the MOT changes come in on 20 May 2018.

I know most of you will be well prepared for the changes, and understand how they will work. However, there's been some misinterpretation in the media about how the new defect categories will work - particularly what will be classed as a dangerous defect.

So, I thought it would be helpful to give a bit more background on the defect categories – explaining what is and isn’t changing.

The legal requirements

For a vehicle to be driven on Great Britain’s roads there are 2 main legal safety requirements for the vehicle. It must be roadworthy and for most vehicles of a certain age, it must have a valid MOT. Whilst they're connected, they're not the same thing, and they both have to be met independently.

So, even if a vehicle is roadworthy, it may not necessarily have an MOT (it isn’t automatic – it needs to go to a garage and get one!). And similarly, just because a vehicle has an MOT, it doesn’t automatically mean it’s roadworthy.  It may have a defect that has come about after the MOT.

I'd like to remind you that this won't be changing on 20 May 2018, vehicles will still need to meet these 2 requirements.

‘Major’ and ‘dangerous’ defects

Currently, a vehicle will either pass or fail its MOT. Testers can then mark defects they believe are dangerous, and make the vehicle owner aware.

From 20 May, the implementation of the new directive will pre-define what is considered as ‘dangerous’. Defects that are failure items but aren’t deemed as ‘dangerous’ will be called ‘major’ defects.

So, after 20 May, defects that are dangerous will be set out for you, and the new ‘major’ term introduced for all other failures.

What ‘dangerous’ defects will mean for motorists

Moving to pre-defined dangerous defects will bring consistency to what is recorded as dangerous. So, we’ve taken the opportunity to make the wording on the MOT failure documents clear in reminding motorists that driving a dangerous vehicle is illegal.

While the majority of your customers would never drive a dangerous vehicle until it’s made safe, we know not everyone will behave responsibly. And, while it isn’t your responsibility to try and physically stop them from driving the vehicle, it’s important you provide them with clear advice that they do have dangerous defects.

This all applies whether the vehicle has a current MOT or not. A dangerous vehicle should never be driven on the road.

An early MOT will still be sensible

Some people have interpreted the changes to mean that a vehicle shouldn’t be brought in for an MOT early. This isn’t true.

We’ll still encourage motorists to not leave their MOT until expiry, as leaving it late increases the risk of the vehicle being used without an MOT or being unroadworthy.

'Minor' defects and advisories

The other new category from 20 May is ‘minor’. This is where there’s a defect on the vehicle – but it isn’t serious enough for the vehicle to fail. Like the major and dangerous defects, they are also pre-defined for you.

And, like the current MOT test, we'll still have advisories. These are very similar to minor defects but rather than a component already being defective, they indicate a component will become defective soon.

Recording defects

We’ve also made changes to the online MOT testing service to try and make it simple for garages to record the new defect types after 20 May.

For most defect areas (for example tyre tread depth) the defect is considered as only one level of severity (major or dangerous). The tester will just pick that the defect is present, and the MOT testing service will automatically include the level (major or dangerous) in the result.

However, for some defect areas (for example, hydraulic brake fluid leaks) there might be defects at more than one level, based on the severity of the defect. Where that’s the case, the wording of the defect describes the difference between major or dangerous.

You should assess which set of words the defect on the vehicle best matches. Then, the MOT testing service will automatically include the level (major or dangerous) in the result.

Launching a training environment

As we mentioned in my previous blog post (Services we're working on), we’re launching a training environment (or prototype area) into the MOT testing service with the post 20 May changes in place.  We'll let you know when it's available.

I’d encourage you to have a look at this when you’re logged into your profile before these changes come into effect.

Finally, if you do see any stories with incorrect information on the changes, please let us know in the comments below.


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  1. Comment by Graham's had enough posted on

    Can i ask why dvsa aren't commenting on, and clearing up all the issues picked up on this blog. I have tried many times to get through on the phones to ask questions / clarify things, but system hangs up on me. In previous posts you have answered questions, but now there is nationwide confusion, this is when we need your help and were being left in the dark! Is there anyone left in the office?? Is the new system that bad that you dont know yourselves???

  2. Comment by david b posted on

    on service brake test- manual states we need to look at how brake application increases and decreases. but i can no longer find failure for brake application uneven or decrease uneven ???

    dvsa is this another item we no longer need to test for?

    • Replies to david b>

      Comment by Julia (DVSA) posted on

      Hi David

      The corresponding RfRs for how brake application increases and decreases are:
      • a brake on any wheel grabbing severely
      • abnormal lag in brake operation on a wheel

      These RfRs replace those for rate of increase/decrease, which were widely misunderstood.

  3. Comment by phil starkey posted on

    also how is fair for a 13plate 1.6tdci focus with a plate limit of 0.55 and a berlingo 1.6 hdi using the same engine have a limit of 1.50 on a smoke test. it's all very well the dvsa bringing in these rules their not the ones who have to argue it out with the customer when their car fails and van passes although the focus manged 0.9 and the van 1.22 just because there is no emissions data on the plate. vw's don't rev so blip not detected is not helping emissions just lower euro 4/5 to 1.0 and have a fair test for all and stop us having the grief

    • Replies to phil starkey>

      Comment by Julia (DVSA) posted on

      Hi Phil
      In exactly the same way as vehicle manufacturers may specify non-default emissions limits for spark ignition engines in the emissions book, they may also have specific limits for compression ignition engines displayed on a plate. We are obliged by the european roadworthiness directive to test to these limits and if the vehicle cannot meet the standard it is because there is a defect with the vehicle.

      This is also in the interest of public health.

  4. Comment by Shaun posted on

    I have noticed that a brake Flexi hose damaged exposing cords is a fail, but there is no mention of a deteriorated hose showing cords as an advisory or fail... . So do we just ignore it if it's showing cords but not damaged?
    Also the manual online clearly stated a reverse lamp not working as an advisory, but I noticed today when i had one not working it was listed as a major? The manual for testers when entering test results has changed but not the online one if not logged in?
    Has there been an update of information? If so are we not being told when there are changes?

  5. Comment by Bert posted on

    what happened to light interference? just had a clio and the rear lights are like a disco (common fault) but now can't fail this.....what a joke

  6. Comment by Harry posted on

    If a diesel vehicle, fails the emission test, with a reading above the manufactures plate value.
    The same vehicle, is then presented for retest, with the plate/sticker removed or illegible. Do we retest to the original limit or default limit???

  7. Comment by Shaun posted on

    Ok so alot of the old diesels seem to have a very low plate limit, some down to 0.7 @ 10 years old, so my query is if one of these fail the emissions, what's stopping the customer bringing the car back with a sticker covering the plate? Would I then have to just test to the 3.0 turbo limit?

  8. Comment by Calum and Dan posted on

    Why is it no longer possible to fail perished/deteriorated flexible brake hoses. The only option is damaged or chafed (which is the same thing) and porous which would mean leaking. Surely if its deteriorated enough to see inside the structure of the hose it should fail as could burst at any time?

  9. Comment by mark posted on

    why has the blog stopped working makes me wonder

    • Replies to mark>

      Comment by DAVID posted on

      Noticed that not 1 of my questions have been answered or got past the adjudicator and very large gaps until new queries come on the blog but very very few are answered

  10. Comment by martin posted on

    when testing a class 1 Yamaha townmate 80cc

    The rear indicators are 16cm apart and the fronts are 22cm apart (measured from the centres ) . They are original manufacture fitment, so do I still have to fail them as they are less than 24cm /30cm respectively??

    I would like someone to clarify this instead of deleting all my comments thanks!

  11. Comment by mark posted on

    I also didn't see any questions about corroded brake pipes

  12. Comment by Mark posted on

    Just done assessment why is there a class 7 question in it when I don't test these we would have s job on getting a 3 axle truck on our ramp

  13. Comment by Graham posted on

    If i have a brake hose deteriorated enough to expose reinforcement i cant fail it, sort it out please! There is only damaged, chafed or twisted!

  14. Comment by Scott posted on

    This is a good one. Advisory for vehicle structure for tow bar mounting eg. rear crossmember/chassis rails is as follows. "Tow bar slightly corroded within 30cm of a tow bar mounting" 😀

  15. Comment by Harry posted on

    Some vehicle, such as a Vauxhall, have an Engine light [small orange engine symbol] and an orange car symbol with a spanner through it, warning light.
    If the EML light is working as it should and the car symbol, light is on. Is that a pass or fail for engine light on?

  16. Comment by Alan posted on

    I first raised this comment on 3rd May re headlight beam obviously incorrect. This has caused major concern from multiple testers and yet DVSA has not replied to any comments. If your aim is to help and assist whilst the system is new surly some form of clarification would be a great help. If it’s now not a failure please let us know so we can clear this matter up. A simple reply is all we want.

  17. Comment by Harry posted on

    Surely, the wording in the inspection manual, should be the same as in the defect categories. An example of this under headlamp aim in the manual 4.1.2
    " The aim of the headlamp is not within limits laid down in the requirements"
    That wording, would work for incorrect beam image, that is no longer available, Why?

  18. Comment by Mark Peter Cole posted on

    No failure anymore for brake hose ferrules but I have had them explode on test before now as they have been totally rotten.Also shock absorber bushes?Do they have to be totally detached in order for them to fail?Headlamp beam image obviously incorrect has been removed.Why?The amount of bulbs that are incorrectly fitted is unbelievable.Handbrake travel little reserve travel?I could go on,but it seems that DVSA needs to address these issues and also make the fail categories more accessible.Why,on earth put C.V gaiters under Body??

  19. Comment by Ken Santi posted on

    3 weeks into the new failure system and I'm still not happy about the handbrake efficiency fail options on a dual line brake system, this is 1 area that most certainly needs looking at !!!!

  20. Comment by Jack posted on

    A tyre:
    load capacity or speed rating not in accordance with the minimum requirements
    load capacity insufficient for axle presented weight
    Copied from the new manual but cannot find the section to fail it on the system

  21. Comment by Jason posted on

    Cannot find where to fail for incorrect load rating for tyres now, one of the testers where I work had car tyres fitted to a commercial van today and neither of us could find it