The MOT Files

The inspection manual, by clause

What the codes on your MOT certificate mean

Manual indexed

Quick answer

Every failure and advisory on an MOT certificate carries a reference like (5.2.3 (e)) — a clause in the MOT inspection manual. This index lists all 555 defect clauses across 119 sub-sections of the car manual, with the official wording, whether each is Minor, Major or Dangerous, how often testers actually record it, and a link to what it means and what puts it right.

Since May 2018 the certificate has quoted the manual directly, so a driver holding one is holding a set of references nobody has indexed for them. Find the number below, or the section it belongs to.

Most recorded

The sub-sections that fail cars most

  1. 5.2.3Tyres12.6 per 100 fails
  2. 5.3.1Springs11.8 per 100 fails
  3. 4.1.2Headlamp alignment9.5 per 100 fails
  4. 5.3.4Suspension joints, pins and bushes7.9 per 100 fails
  5. 3.4Windscreen wipers7.6 per 100 fails
  6. 2.1.3Steering linkage condition7.5 per 100 fails
  7. 3.5Windscreen washers6.6 per 100 fails
  8. 1.3.2Efficiency5.3 per 100 fails
  9. 5.3.2Shock absorbers4.8 per 100 fails
  10. 8.2.1.2Gaseous emissions3.9 per 100 fails
  11. 1.2.1Performance3.8 per 100 fails
  12. 1.1.11Rigid brake pipes3.4 per 100 fails

Section 0

Identification of the vehicle

Section 1

Brakes

Section 2

Steering

Section 3

Visibility

Section 4

Lamps, reflectors and electrical equipment

Section 5

Axles, wheels, tyres and suspension

Section 6

Body, structure and attachments

Section 7

Other equipment

Section 8

Nuisance

Source

Where this comes from

Clause numbers, wording and categories are reproduced from the MOT inspection manual for cars and passenger vehicles, published by the Driver and Vehicle Standards Agency and licensed under the Open Government Licence v3.0. Frequencies are from the DVSA anonymised MOT testing dataset, class 4 tests, and count items per 100 failed tests. Explanations are ours. Sections 9 and 10 apply only to buses and minibuses and are not indexed.

Common questions

What do the numbers in brackets on my MOT certificate mean?
They are clause references to the MOT inspection manual, the document every tester works from. "5.2.3 (e)" means section 5 (axles, wheels, tyres and suspension), sub-section 5.2.3 (tyres), defect (e) — tyre tread depth not in accordance with the requirements. Every failure and advisory on a certificate issued since May 2018 carries one, and each is listed here with its official wording.
What is the difference between a Minor, Major and Dangerous defect?
Dangerous: a direct and immediate risk to road safety or the environment. The vehicle fails and must not be driven until repaired, even to a garage. Major: a defect that affects safety, the environment or other road users. The vehicle fails. Minor: a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Only Major and Dangerous defects fail the test. The category is fixed by the manual for each clause, not chosen by the tester.
Is the wording here the same as the official manual?
Yes, reproduced exactly. The manual is published by DVSA on GOV.UK under the Open Government Licence and this index was built from it on 2026-09-03. Alongside each clause we add two things the manual does not have: how often it is actually recorded across 33 million tests, and a plain-English explanation of what it means and what puts it right.
Why does the same fault appear under several clauses?
Because the manual grades severity. A worn brake disc is 1.1.14 (a)(i) if significantly worn (Major) and (a)(ii) if likely to fail (Dangerous). A tyre cut deep enough to reach the cords is 5.2.3 (d)(i); a bulge or exposed cord is (d)(ii) and Dangerous. The letter tells you how serious the tester judged it.