Skip to main content
MOT Reference

The MOT Encyclopedia

A working reference to the MOT test, written for owners and tester candidates

The MOT test inspection manual is a long, technical document. This encyclopedia is the working version: each section explained in the order a tester walks around the vehicle, with the defect categories drawn directly from the DVSA Class 3, 4, 5 and 7 inspection manual. It is written so an owner can use it to prepare a car for test, and so a candidate tester can use it as a study companion alongside the official manual.

Contents

  1. Chapter 1 — What the MOT is, and what it is not

    9 min

    The legal basis of the MOT, the defect categories, who can test, and the common misunderstandings owners bring to the test bay.

  2. Chapter 2 — Section 1: Lamps, reflectors and electrical equipment

    4 min

    Headlamp aim, sidelights, indicators, hazard warning, rear fog, registration plate lamp, and how each is inspected.

  3. Chapter 3 — Section 2: Steering and suspension

    5 min

    Track-rod ends, ball joints, anti-roll bar links, shock absorbers — the play tests, the visual checks, the defect thresholds.

  4. Chapter 4 — Section 3: Brakes

    4 min

    Roller brake test thresholds for service and parking brake, imbalance limits, ABS warning, brake pipe and hose inspection.

  5. Chapter 5 — Section 4: Tyres and road wheels

    5 min

    Tread depth, sidewall damage, load index, speed rating, mixing of tyre types on the same axle, and what's a Dangerous defect.

  6. Chapter 6 — Section 5: Seat belts and supplementary restraints

    5 min

    Anchorage condition, locking mechanisms, retractors, airbag warning lights and pre-tensioner indicators.

  7. Chapter 7 — Section 6: Body, structure and corrosion

    5 min

    Prescribed areas, the 30cm rule around mounting points, when underseal hides what the tester needs to see.

  8. Chapter 8 — Section 7: Exhaust, fuel and emissions

    5 min

    Petrol, diesel and hybrid emissions limits, the smoke meter, EGR and DPF related advisories.

  9. Chapter 9 — Becoming a Nominated Tester

    5 min

    Eligibility, the DVSA training course, the demonstration test, annual assessment and CPD requirements.