What does 3.1 mean on an MOT certificate?

It refers to sub-section 3.1 of the MOT inspection manual, "Field of vision", within section 3, visibility. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 5 listed here. 1 of them is graded Dangerous, 3 Major and 1 Minor.

Which field of vision defect is recorded most often?

"An obstruction significantly affecting the driver’s view of the road through the swept area of the windscreen or an obligatory external mirror not visible" (3.1 (a)(ii)), recorded about 0.0 times per 100 failed MOT tests nationally. We explain what it means and what puts it right.

Does a Minor defect fail the MOT?

No. a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Major and Dangerous defects fail. A Dangerous defect also means the car must not be driven until it is repaired.

Section 3 · Visibility

3.1 Field of vision

Manual indexed 3 September 2026

Quick answer

Sub-section 3.1 of the MOT inspection manual covers field of vision and lists 5 defects, 1 of them Dangerous. A reference like "(3.1 (a)(i))" on a certificate points to the matching row below. The most recorded is "An obstruction significantly affecting the driver’s view of the road through the swept area of the windscreen or an obligatory external mirror not visible", about 0.0 times per 100 failed tests.

Official wording

The defect clauses

3.1 (a)(i)Minor
An obstruction within the driver’s field of view that significantly affects his view in front or to the sides outside the swept area of windscreen
3.1 (a)(ii)Majorunder 0.1 per 100 fails
An obstruction significantly affecting the driver’s view of the road through the swept area of the windscreen or an obligatory external mirror not visible
Mirror missing, damaged or insecure explained: what it means and what puts it right
3.1 (b)(i)Major
A bonnet which cannot be safely secured in the closed position
Door or boot will not close securely explained: what it means and what puts it right
3.1 (b)(ii)Dangerousunder 0.1 per 100 fails
A bonnet seriously at risk of opening inadvertently
3.1 (c)Majorunder 0.1 per 100 fails
A bonnet primary retaining device excessively deteriorated, ineffective or insecure
Door or boot will not close securely explained: what it means and what puts it right

Wording and categories reproduced from the DVSA inspection manual under the Open Government Licence. Frequencies are items per 100 failed class 4 tests across the DVSA anonymised MOT dataset; a clause with no figure was not recorded often enough to appear in any model’s top forty failure items. 3 of 5 clauses link to our own explanation.

Grading

What the categories mean

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.

The full guide to defect grading

Section 3

Other sub-sections of visibility

All sections of the manual

Common questions

What does 3.1 mean on an MOT certificate?: It refers to sub-section 3.1 of the MOT inspection manual, "Field of vision", within section 3, visibility. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 5 listed here. 1 of them is graded Dangerous, 3 Major and 1 Minor.
Which field of vision defect is recorded most often?: "An obstruction significantly affecting the driver’s view of the road through the swept area of the windscreen or an obligatory external mirror not visible" (3.1 (a)(ii)), recorded about 0.0 times per 100 failed MOT tests nationally. We explain what it means and what puts it right.
Does a Minor defect fail the MOT?: No. a defect with no significant effect on safety or the environment. Recorded on the certificate; the vehicle passes. Major and Dangerous defects fail. A Dangerous defect also means the car must not be driven until it is repaired.