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Highway Code

Highway Code, Annex 6. Vehicle maintenance, safety and security (part 1)

Annex 6. Vehicle maintenance, safety and security. A legal requirement (MUST / MUST NOT).

  • Annex 6. Vehicle maintenance, safety and security
  • Legal requirement
  • OGL v3.0

What the rule says

Law · MUST

Take special care that lights, brakes, steering, exhaust system, seat belts, demisters, wipers, washers and any audible warning systems are all working. Also

  • lights, indicators, reflectors, and number plates MUST be kept clean and clear
  • windscreens and windows MUST be kept clean and free from obstructions to vision
  • lights MUST be properly adjusted to prevent dazzling other road users.
  • Extra attention needs to be paid to this if the vehicle is heavily loaded
  • exhaust emissions MUST NOT exceed prescribed levels
  • ensure your seat, seat belt, head restraint and mirrors are adjusted correctly before you drive
  • ensure that items of luggage are securely stowed. Laws RVLR 1989 regs 23 & 27, & CUR regs 30 & 61 Warning displays. Make sure that you understand the meaning of all warning displays on the vehicle instrument panel. Do not ignore warning signs, they could indicate a dangerous fault developing.
  • When you turn the ignition key, warning lights will be illuminated but will go out when the engine starts (except the handbrake warning light). If they do not, or if they come on while you are driving, stop and investigate the problem, as you could have a serious fault.
  • If the charge warning light comes on while you are driving, it may mean that the battery isn’t charging. This should also be checked as soon as possible to avoid loss of power to lights and other electrical systems. Window tints. You MUST NOT use a vehicle with excessively dark tinting applied to the windscreen, or to the glass in any front window to either side of the driver. Window tinting applied during manufacture complies with the Visual Light Transmittance (VLT) standards. There are no VLT limits for rear windscreens or rear passenger windows. Laws RTA 1988 sect 42 & CUR reg 32 Tyres. Tyres MUST be correctly inflated to the vehicle manufacturer’s specification for the load being carried. Always refer to the vehicle’s handbook or data. Tyres should also be free from certain cuts and other defects. Cars, light vans and light trailers MUST have a tread depth of at least 1.6 mm across the central three-quarters of the breadth of the tread and around the entire circumference. Motorcycles, large vehicles and passenger-carrying vehicles MUST have a tread depth of at least 1 mm across three-quarters of the breadth of the tread and in a continuous band around the entire circumference. Mopeds should have visible tread. Be aware that some vehicle defects can attract penalty points. Tyre age. Tyres over 10 years old MUST NOT be used on the front axles of:
  • goods vehicles with a maximum…

Rule text reproduced verbatim from the official Highway Code (Crown copyright) under the Open Government Licence v3.0, see the attribution at the foot of this page.

In plain English

Stripped of the formal wording, this guidance comes down to one idea: take special care that lights, brakes, steering, exhaust system, seat belts, demisters, wipers, washers and any audible warning systems are all working. Because it is written with “MUST” or “MUST NOT”, it carries the force of law, ignore it and you are committing an offence, not simply driving badly.

It belongs to the annex 6. vehicle maintenance, safety and security part of the Code, the habits a confident, considerate driver builds until they are automatic. The aim is not to memorise the sentence word for word, but to understand the hazard it protects you from, so you apply it without having to think when it counts.

If you are learning, treat this rule as one piece of a connected set rather than an isolated fact. The related rules below sit in the same section and reinforce each other, reading them together is how the annex 6. vehicle maintenance, safety and security part of the Code starts to feel like common sense rather than a list to revise.

Because this is a legal rule, the consequences of ignoring it reach beyond the test: a “MUST” or “MUST NOT” breach can mean a fixed penalty, points on your licence, or in serious cases prosecution. Either way, the safe move is to build the habit early, while a driving instructor can correct it, rather than relearning it under test pressure. That is exactly what the practice routes and coaching in the DriveRoutes app are designed to help with, turning the rules below into the way you naturally drive.

Why this rule matters on the road

Following this rule keeps your driving predictable and safe, which is what every other road user is relying on. It is one small part of the habit-set that, taken together, prevents the everyday mistakes that cause collisions.

Common faults examiners record

In the annex 6. vehicle maintenance, safety and security part of the Code, the faults most often written on the marking sheet tend to be the same handful. Knowing them in advance is the quickest way to drive them out of your own habits:

  • Acting too late because the situation was read close rather than early.
  • Incomplete observation before committing to a manoeuvre.
  • An unsuitable speed for the road, the traffic or the conditions.

On the day

On the day, applying Highway Code, Annex 6. Vehicle maintenance, safety and security (part 1) is about doing the safe, deliberate thing slightly earlier than feels necessary: read the situation in good time, observe fully, and act smoothly. The examiner is looking for planned driving, not perfection, and good habits formed in lessons carry you through.

Quick checklist

  • Read the situation early and plan your response.
  • Observe fully before you commit to anything.
  • Keep your speed suitable for the road and conditions.

More from Annex 6. Vehicle maintenance, safety and security

Related Highway Code rules

Highway Code, Annex 6. Vehicle maintenance, safety and security (part 1), your questions

Take special care that lights, brakes, steering, exhaust system, seat belts, demisters, wipers, washers and any audible warning systems are all working. It is a legal requirement, it uses “MUST” or “MUST NOT”, so breaking it is a criminal offence that can mean a fine, penalty points, or disqualification.

DriveRoutes is an independent study aid and is not affiliated with, endorsed by, or connected to the Driver and Vehicle Standards Agency (DVSA).