# Braking system component modification adversely affecting braking performance — Vehicle inspection defect categories: MOT major, minor and dangerous verdicts

For Braking system component modification adversely affecting braking performance, category is Dangerous; inspection item number is 1.1.21; defect reference is (d)(ii); inspection item is Complete braking system; authority is DVSA MOT (cars, vans and passenger vehicles, classes 3, 4, 5, 7), recorded from its source on 2026-08-06.

- **Defect:** Braking system component modification adversely affecting braking performance _(verified: appears in the quote below)_
- **Category:** Dangerous _(verified: appears in the quote below)_
- **Inspection item number:** 1.1.21
- **Defect reference:** (d)(ii) _(verified: appears in the quote below)_
- **Inspection item:** Complete braking system
- **Authority:** DVSA MOT (cars, vans and passenger vehicles, classes 3, 4, 5, 7) _(our reading, not quoted from the source)_

## What the source says

> (d)(ii) | Braking system component modification adversely affecting braking performance | Dangerous

## Source

- https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/1-brakes

Last verified: 2026-08-06. Review by: 2027-02-02.
Part of [Vehicle inspection defect categories: MOT major, minor and dangerous verdicts](https://referencesource.org/vehicle-inspection-defect-categories/).