The MOT Files

Section 1 · Brakes

1.1.9 Pressure storage reservoirs

Manual indexed

Quick answer

Sub-section 1.1.9 of the MOT inspection manual covers pressure storage reservoirs and lists 5 defects. A reference like "(1.1.9 (a)(i))" on a certificate points to the matching row below.

Official wording

The defect clauses

  1. 1.1.9 (a)(i)Minor

    Reservoir has minor damage or corrosion

    Corrosion in a structural area explained: what it means and what puts it right

  2. 1.1.9 (a)(ii)Major

    Reservoir heavily damaged, heavily corroded or leaking

    Brake servo or vacuum system defective explained: what it means and what puts it right

  3. 1.1.9 (b)(i)Minor

    Drain device on an air brake system operation affected

  4. 1.1.9 (b)(ii)Major

    Drain device on an air brake system inoperative

  5. 1.1.9 (c)Major

    Reservoir insecure or inadequately mounted

    Brake servo or vacuum system defective 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 1

Other sub-sections of brakes

All sections of the manual

Common questions

What does 1.1.9 mean on an MOT certificate?
It refers to sub-section 1.1.9 of the MOT inspection manual, "Pressure storage reservoirs", within section 1, brakes. The letter or letters after it — (a), (b)(i) and so on — identify the specific defect from the 5 listed here. 3 Major and 2 Minor.
Which pressure storage reservoirs defect is recorded most often?
None of the clauses in this sub-section appears among the most-recorded failure items nationally; they are rare in practice.
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.