Failed Your MOT? What Dangerous, Major and Minor Actually Mean

An MOT certificate used to be simple: pass or fail. Since May 2018 every problem the tester finds is put into one of four categories, and the category decides whether the car passes, whether it fails, and whether you can even drive it home.

Here is what each one means, in plain English, and what to do next.

The four categories at a glance

Category	Result	Can you drive it?
Dangerous	Fail	No. Not until it is repaired.
Major	Fail	Only if your old MOT has not run out, and only to get it repaired
Minor	Pass	Yes, but get it repaired soon
Advisory	Pass	Yes. It is something to watch.

Dangerous

A dangerous defect is a direct and immediate risk to road safety or has a serious impact on the environment. Typical examples are a tyre with the cords showing, a brake that barely works, a steering joint that is about to separate, or a fuel leak.

The car fails, and you must not drive it away until the fault is fixed. This applies even if your old certificate still has weeks left on it. Driving a vehicle in a dangerous condition can mean a fine of up to £2,500, three penalty points and a driving ban. If the car fails with a dangerous defect, it is usually simplest to let the garage that tested it carry out the repair there and then.

Major

A major defect could affect the safety of the car, put other road users at risk, or harm the environment. This is where most MOT failures fall: worn brake pads or discs, a blown headlight bulb, a split CV boot, tyres below the legal tread, or an exhaust that is blowing.

The car fails. Whether you can drive it depends on your old certificate:

• If your previous MOT is still valid (for example, you tested a couple of weeks early), you can drive the car, as long as it is roadworthy, to have the repair done. The old certificate stays valid until it expires.
• If your previous MOT has already run out, you can only drive it to a place where it will be repaired or to a pre-booked MOT test. Driving it anywhere else risks a fine of up to £1,000, and your insurance may not cover you.

Either way, a major defect is something to fix now, not after the weekend.

Minor

A minor defect has no significant effect on safety or the environment, but it is still a fault. A small chip in the windscreen outside the driver’s line of sight, a slightly loose number plate or a number plate lamp out are typical examples.

The car passes, and the minor defects are listed on the certificate. You do not have to fix them before driving, but you should repair them soon. Left alone, a minor fault can easily become a major one by the next test.

Advisory

An advisory is the tester’s note that something is starting to wear and will need attention. "Front tyres close to the legal limit", "brake pads wearing thin" and "slight corrosion on brake pipes" are common ones.

Advisories do not affect the result, but they are some of the most useful information you will get all year. They tell you what is likely to fail next time, and roughly when you will need to spend money on the car. You can see the advisories from your car’s previous tests for free on GOV.UK, which is also a sensible thing to check before you buy a used car.

Retests: how to avoid paying twice

If the car fails, you will need a retest once it has been repaired. The rules decide whether you pay again:

• If the car stays at the test centre for the repair and is retested within 10 working days, the partial retest is free.
• If you take it away and bring it back to the same test centre by the end of the next working day, the retest is free for a set list of items, such as lights, wipers, tyres, number plates and seat belts.
• If you bring it back within 10 working days for anything else, you can be charged for a partial retest, but no more than half the full MOT fee.
• After 10 working days, it needs a full MOT again.

That is a good reason to have the car tested somewhere that can also carry out the repairs, and to book the MOT early enough that a fail does not leave you without a car.

You can test up to a month early

You can have the MOT done up to a month, minus a day, before the current certificate runs out, and keep the same renewal date. Testing a few weeks early means a fail leaves you with a valid certificate while the repairs are done. If you are not sure when yours is due, check your MOT date here.

Frequently asked questions

Does a minor defect mean the car failed?

No. Minor defects and advisories are both passes. Only dangerous and major defects fail the car.

Can I drive home after a major fail?

Only if your old MOT is still valid and the car is roadworthy, or if you are driving straight to a garage for the repair. If there is a dangerous defect as well, you cannot drive it at all.

Do advisories have to be fixed?

Not by law. But they are an early warning, and fixing them before the next MOT is almost always cheaper than waiting for them to become a fail.

Is the MOT the same as a service?

No. The MOT checks that the car meets minimum safety and environmental standards on the day. It does not change the oil, filters or anything else. Booking both together is common, and we have written about why combining them saves time.

MOT testing in Letchworth

We test cars at our workshop on Protea Way, and if anything fails we explain it in plain English, show you the part if you want to see it, and quote for the repair before any work is done. Book your MOT online.

Dom’s Garage Services, 11 Protea Way, Letchworth Garden City, SG6 1JT. Book online or call the workshop on 01462 671753.